A little late to get this out, but I played the Overwatch 2 tech beta while it was available and it's surprising how similar and different it feels all at once.
Obviously these are early days, and I'm sure we'll see a lot more changes come before the game officially launches, but it does seem like it could've just been an update to the original game.
I get why they're doing it that way - Overwatch has been out for year now, and patches don't bring new players in like a launch does. And despite how hasn't changed, the game does feel quite different with the various balance changes and new 5v5 format.
If Overwatch 2's launch isn't a great one though, I wonder how many players will stick around once it's out, since that will signal the coming end of support for the original game.
We shall see how it goes!