0.75% of users on Steam have the same resolution as you which equates to over 100,000 people - I doubt they all have performance problems.
Perhaps your setting the wrong graphics options in your games.
It does take some tweeking in some games. Also I forgot to mention I'll be doing a little spread sheet with the titan vs 2080ti in 2 separate machines 8700k@5ghz and a 6800k @4.4ghz at 1080p and 3440x1440