This is what I've found after 15 years of working out and athletics. Think of it this way: doing the same thing over and over again is what is proven to lead to workplace injuries. Doing the same thing over and over again in the gym is no different.

I like to do a weight training as the consistent foundation, with a mix of heavy lifts, calisthenics, volume (bodybuilding) training and mobility training. Add in some yoga, rock climbing, biking, soccer. I feel this sort of mix balances movements out which helps with injury prevention and also makes sure you always have something active to do that you enjoy, which is definitely #1.

Is there any evidence this is at all bad in the weight room? It isn’t repeated at enough volume and if you have a diverse enough full body routine making everything stronger including connective tissue it would not matter. Changes in load are a better predictor for injuries in studies I have read.

I’m mostly talking from personal experience. I imagine an actual well powered study on this sort of thing would be hard to do, for similar reasons a lot of fitness / nutrition studies are not great. I agree that a good diverse full body routine would help mitigate injury risk vs a less diverse routine. Obviously diminishing returns but expanding outside of the weight room is IMO also helpful for injury prevention if not quality of life. Pertinent video: https://youtu.be/rb2DPHi39FU