I went through a phase of indoor climbing and bouldering lots a few years ago - covid shutdown stopped me going and have barely been back since for various reasons. When I was climbing lots it was clear that the people who all but live at the wall (and/or start really young) tend to be the epic climbers. A lot of it is practicing technique and adapting your body - I’m definitely nowhere near as good now as I was pre pandemic.
As for watches - I’d go bare wristed. Most walls have clocks and I wouldn’t want to scratch up or worse get an injury from snagging a watch. I tried using my garmin’s indoor climbing mode once, but the stats didn’t add anything to the experience and it was a massive faff to enter the route grade and remember to start and stop it each time.