Lets try it a different way... Your thread asks the question "why do people fear MIM" but it seems that is not really what you want to discuss. Maybe a better title would have directed the discussion that would have suited your intent better.
You end the OP with:
I have given you a few answers but I will summarize them for the sake of clarity.
1. The first company to full embrace the MIM technology to the level where people understood that there were powder parts in their gun was Kimber. They started with what was IMHO proper usage, quality and QC of MIM parts in order to deliver a semi-custom gun at stock price. Unfortunately cost cutting and volume added to poor QC lead to breakages. Then even worse customer service of broken pistols served as one of the origins of the "fear of MIM" parts.
2. Companies, even gun companies, have a long history of cost cutting in order to inflate profits, which is the goal of every company, or to meet a price point. This creates a environment of mistrust between the consumer and the corporation making almost every product produced these days not just guns. MIM parts are an easy tangible example which people can focus on because as other posters have mentioned you can "see" that a MIM part is different then tooled steel. It looks different and therefore is perceived as cheap or inferior.
3. More and more outsourcing of small parts in a race to the bottom scares people because the source of the parts is unknown and the quality of the parts is unknown. As more and more small parts move to MIM that means fewer and fewer guns are being produced "in house" and the company whose name is on the gun is perceived to have has less control over the QC then they did in the past.
4. Yes some people are old fashioned and simply want everything built the way it used to people. Call them purist call them snobs call them antiquated. Whatever terms you want to use but in the end these people know what they like and want seek it out and for the most part are willing to pay what the market demands as a result of their preferences.
5. People like myself have seen MIM parts fail. It is not that we have not see non-mim parts fail it is that the failure of MIM parts is always catastrophic. Thumb safeties shear right off the frame and sights simply disappear while firing.
I will add these to the mix:
6. A lot of people do not understand the MIM process and its real life applications. They are not involved in the field or have not done enough reading and research to understand the process and its past, current and proposed future uses. Lack of understanding often leads to mistrust.
7. Almost every product today is designed to meet a price point. This is the one that personally scares me the most and it is IMHO the other side of the coin to the penny pitching for profit. Products are no longer designed for performance and then priced based on what it took to build it. In today's price point driven consumer economy very few companies set out to make the best anything. Sig wanted to make a .380 auto pistol with a street price of around $450 you get the P238. Ruger wanted to make a sub $700 1911 that looks like a $2500 one you get the SR1911. In doing so companies make design and part compromises which may or may not impact the consumer. Unfortunately all to often these compromises do impact the consumer. We see this playing out in across the spectrum of manufacturing not just guns. At least guns are not as bad as cars in this respect.
These are just some of the reasons people "why people fear MIM" which was your original question wasn't it? The funny part about this thread is that you really don't seem to want to know about "why people fear MIM" as much as you want to prove to people they shouldn't fear MIM. Maybe a different title would have suited your purpose better.
In the end I think MIM is here to stay. Is it a good thing or a bad thing only time will tell. Personally I am indifferent and believe it is here to stay and as you have alluded to this process will allow gun makes to keep making guns and for people to keep buying guns. The majority of people will not pay for tooled steel in guns anymore. Many of today's designs do not demand it. Some of the older designs do not require it. I can say that it is getting harder and harder everyday to get a NIB gun that does not have some amount of MIM in it. Even Wilson Combat uses MIM sears in some of their guns IIRC. I fully accept the reality and role MIM playing in guns today and will continue to play in the future.
Anyone who has spent anytime looking into MIM knows here is good MIM and bad MIM just like there is good and bad of just about any process. I believe it is universally understood that MIM when applied and manufactured properly can get the job done. That is almost never the real point of contention in these MIM threads.
In the end I think the weakness in the MIM process is quality control. Most gun companies are farming out the MIM parts production to MIM houses do to the cost of tooling it up themselves. People read or hear on the news every single day about an parts manufacture issues in cars and other manufacturing. This leads to a "fear" of the QC process which has been validated in the gun industry by Kimbers teething issues. It is not the MIM process in and of itself that is "feared" it is the miss-application of its use to meet a price point or for profit, its outsourced nature and at this point in time a perceived lack of attention to detail and poor QC.
The best part about my signature tag and putting it in bold is that I am not an MIM hater. I have plenty of guns in the safe with MIM parts. I do not "fear" it as much as I prefer designs which do not require it. I prefer my 1911s not to have any but honestly some do. I even have one with a cast frame!!!!! LOL
If I am paying a premium for what is perceived as a premium product I prefer no MIM. If I am buying sub $500 tactical plastic I expect and accept MIM.The bolding of that statement was to highlight that just because I am taking this position does not mean I have completely accepted it. I do not fully accept the MIM "fear" as you call it but I do understand where the "fear" comes from and why it exists. I was referring to my position in this thread not yours.
Have a great Sunday.