I like the sweat guard on mine because I’ve found my shirts don’t get trapped betwen the gun (Glock, PPQ) and holster. Never noticed any impediment to the draw stroke.
Galco Royal Guard has been the gold standard for IWB 1911 holsters for decades…no sweat guard and nobody complained.
I wouldn’t worry about it too much. Being left handed, my safety is always “exposed”.
Definitely not
I have been carrying a 1911 for a lot of years and have not had the thumb safety sweep off unless I did it intentionally. I did have the outside thumb safety break off while fighting with a suspect on a concrete surface, but the safety remained in the safe position.
If the safety is swept off for any reason while you are carrying, jogging, lugging furniture, etc., you still have the grip safety in play. In the extreme unlikelihood the thumb and grip safety both fail, the holster is still covering the trigger.
The 1911 is a whole lot safer than most realize.
I would concern myself with retention, comfort and body oils/perspiration attacking the metal when selecting a good holster. You may also want to consider if the holster will protect you if you fall on your weapon side. It’s happened to me and it can be pretty painful.