All things are relative, of course.
A semi-auto .380 pistol - such as a Beretta 84 - will almost certainly have less wear & tear than even a Ruger .44 magnum.
But let's compare "apples to apples" a bit.
Compare that .380 vs. a quality .38 Special - a stainless S&W M67 - both fired with standard velocity jacketed ammo. If neither gun is fired rapidly then you'll grow old and gray waiting for something to need repair.
9mm vs. the .357 Mag -- sort of apples to pears here.
Both are high pressure rounds. If we presume some moderate mix of 9mm+P then the likelihood of failure, I think, goes to the 9mm pistol if the .357 is an S&W L-Frame or N-Frame.
One of my long time friends owns a S&W Model 28 Highway Patrolman. Big honking N-Frame. After approximately 24,000 of mostly 158gr .357 ammo it required new cylinder hand & stop (bolt). He also replaced the springs at that time. Last I talked to him (circa 1998) the gun had over 38,000 rounds through it.
I have a maintenance sheet from the US Army (1955) that recommended replacing parts on a 1911 as follows;
5000 rds max - recoil spring
15000 rds max - Springs - Recoil, main, sear spring, firing pin spring; spring guide,
30000 rds max - all springs, recoil spring guide, barrel bushing, extractor, ejector, slide stop & safety plungers, firing pin.
And there were a host of items to inspect at 15 & 30k rounds too.
The semi-auto pistol is designed to allow many parts to "drop in" as replacements. But if you are staking your life on the gun, you'll let a gunsmith check the fit and function of each replacement part. Thus, I'd say the Auto will see the gunsmith first.
If your habit is to rapidly fire your revolver (e.g. about 2 rds per second) the cylinder stop notches and cylinder stop can become excessively worn.
Improper lubrication can wear out parts too. A dry semi-auto pistol can produce excessive rail wear in 300-500 rounds in rapid fire conditions. Use of +P ammo or +P+ ammo can damage the locking lugs in the slide or barrel.
With money being no object, the Semi-Auto pistol can be supplied with new parts easier than a revolver as long as the frame and slide aren't damaged. So can the revolver be repaired, though some guns require more gunsmithing than others.