I know I was excited 20 years ago when I got the 92d kramer iwb3 ever made for my beretta 92. They’ve changed production sequences though, I have one now that says Px4C on it well at least one is a collectors item.
It will lose that rigidity over time. Not immediately and not all at once, but eventually. It's then you start to see issues with it falling into the holster mouth.
For concealed carry I am fine with a good friction fit alone. I understand others needs may vary, and I do have some retention holsters for certain activities. FWIW, I moved away from a thumb snap for a few reasons, including needing to toss them once the strap becomes unsatisfactory. Personally I find the ALS type holster much easier to activate at speed 100% of the time and I've yet to wear one out. I know the options with one are much more limited for that system vs a thumb strap.
Sorta around sometimes for some of your shitty mod needs.
While reholstering, if you use your trigger finger to sweep and push the thumb break strap down the outside of the of the holster, you will avoid three common pitfalls of thumb breaks.
A) trying to reholster into a snapped holster.
B) strap inside of the trigger guard sending a bullet down your leg.
C) what really happens when people claim B) reholstering with your finger on the trigger.
Whether you think you can or you can't, you're probably right.
Since I’m not articulate here’s a quick demo of what I was talking about. If you trap the thumb break strap with your trigger finger, you’ll solve the real problem of finger in the trigger guard and clear the strap.
Whether you think you can or you can't, you're probably right.