I carry ankle/boot style many times. But it's got to be with the right gun. I carry my PPK 32acp that way the majority of the time when I carry that gun. I use a small holster with a clip on it for normal owb carry,and clip it on the inside of my boot. I then have a wide piece of elastic/velcro around the holster/clip that goes around my calf. This makes it secure, and clipped on the boot with the gun on the inside, makes it so it can't slide down and become uncomfortable on my ankle. If it's a small/light enough gun, it's very comfortable and doable. And there are many times where that is indeed the best way to carry the gun.
There is no "Right or Wrong" way to carry a gun. And anyone that implies there is, is wrong. Each person is different, and what works for them is all that matters. And for what it's worth, your gun is NOT your primary defense against an attack or threat. Actually, it is your LAST defense. Your brain is your primary defense against a threat. If you use your brain correctly, you will have plenty of time to get to your gun if needed. If the scenario is such that you didn't have time, and the threat came upon you too quickly, then chances are that you wouldn't have had the time to get to your weapon no matter how it was being carried. And there are times when confronted with a threat, that it's better to not draw your weapon. A person with a gun pointed straight at you, is not the time to decide to pull your gun. You will most likely be shot. And believe it or not, sometimes: "Here's my wallet is the right answer". Sometimes, you can create opportunities to allow you to respond in force.
But bottom line is: carry in a boot/ankle combination is definitely doable. Especially for some of us who wear boots every day. We don't wear them as a fashion ensemble. They are as natural to us as sneakers are to some people. And therefor, you can adapt a gun to them quite easily. But it's not going to be a colt 1911 commander. The weight will become an issue. There's plenty of 32acp/380/and possibly a couple of 9mm that work fine. And a taurus 709 slim seems to be one that could work just fine. Get the smallest holster that is full, (Meaning the barrel isn't out the bottom rubbing you), clip it on the inside of your boot. (Opposite boot as your shooting hand. Inside of leg, not outside of leg where it can get bumped). Elastic/velcro around the holster and your calf. Loose fitting jeans. Works fine with my Ariat boots. Been carrying my 32acp like that for many years. And remember; we don't get into gun fights. That is hollywood. Our guns are for defensive purposes. IF we pull that gun out, it's not to scare anyone. And it's not to dive behind a dumpster and get into a hollywood gun fight. If we pull the gun, it's because we have a target. We are going to aim/point at that target. And we are going to unload that magazine into that target. Until that target is no longer a threat. The only way I WON'T fire a round, is if at the time the gun is up to my eyes when I'm pointing/aiming, I see their back. If I see their back, they are going the other way, and I'm not shooting. If I see their front, I WILL shoot. If I didn't plan on shooting, I never would have pulled the weapon out.