Every rank is like catastrophically more difficult to get through than the previous, which most ppl don’t believe but it’s true. I barely got into masters, but my hero pool (essentially Ashe with some other random dps like junkrat occas) is essentially unworkable for climbing in masters.
I’ve since gone back to gold\plat trying to learn genji\tracer\widow etc more appropriate heroes for high diamond and masters. It’s like 160 hours on Ashe last season only to have to go back to zero and learn different heros for that elo. I’m spending this entire season on genji hoping to make some progress but it requires me to one trick all the way through gold->plat->diamond-> masters even to add him to my hero pool. Like I plan to probably play 100 hours genji this season with some VOD reviews to figure him out. The hope is to just get another hero into masters so that I have a second go to hero for that level. Problem is Ashe can potentially get eaten by good widows or if the enemy is divey enough this can be an issue also.
Essentially the dps heros that “work” in masters are totally different than the ones that “work” in plat and diamond so if you hero pool is either too shallow or relies on low skill heroes, you have to go back to ground zero once you get there and rebuild with different heroes more appropriate for that elo.
One of my favorite videos on OW that explains why you shouldn’t play reaper, etc hero traps.