I used to think that too… Until I made an account and started playing DPS… I only really saw what it was like on the other side after I joined them. I wasn’t that bad either, constantly high plat.
Game was new, everyone had to figure out how to play this game. Plus Ana was so horrendously OP, there were not many Mercys in the matches. As soon as Ana became trash and people shifted to Mercy, many people realized how problematic mass rez was.
Same as now people start to realize how problematic Doomfist is with him being decently played now. Same with Widow as people started to get good with her, she was always a trollpick who was pushed down by Dive, once Dive was gone, Widow roams and everyone realized she’s too good, hence the grapple nerf.