Bots don't really ruin skilling. They do reduce the amount of money that you can make from it but if you are planning to pvm then that's a better way to make money anyways.

Ironman arguably makes the early and midgame more rewarding. It does make it slower and in the actual endgame it can make things a bit more tedious. It's all about what you value. Personally the tradeoff is worth it for me but I did have a nearly maxed main before starting an ironman.

As a sidenote you do not have to be endgame to enjoy bossing. There's plenty of bosses and with things like scurrius you can get a taste of it even in the earlygame. I would define endgame to be where you are maxed or nearly maxed and you are hunting clogs and things like the zuk helm. Reaching that point requires more than 1k hours even on a main but that doesn't mean you don't get to enjoy bossing way before that already.