First, we saw them bring back the blue fire that showed up after you were playing well (what we already had in OW1). Then we saw them revert the changes they made to the competitive system, showing us our SR after every win/loss again. (What we already had in OW1). Now we’re seeing them remove heroes from the battlepass, making them free once again (what we already had in OW1). We’re playing catch-up, FFS!
Even if they decided to bring back the border leveling system, the end of match stat cards, and the LFG and innovated upon these systems and made them better than they once were, it still wouldn’t be enough to justify the 2 on Overwatch’s title.
I get that, for some, it seems like such a trivial thing, but the principle of it does matter. There are so many people who spit on the game just for the “2” alone.
“Overwatch? You mean that game where they took away features, started charging for skins, and then slapped a 2 on the title? Yeah, no thanks!”
Blizzard can change that stigma by being truthful, admitting the game is not a sequel, and removing the 2. 
Make Overwatch great again! 
