You may have picked up a fan.
I looked at the reputation over time plots for the 36 highest reputation users (the first page of users, sorted by all time reputation), and I don't see any others with such an inflection point. I likewise looked at the users with reputation ~10k (i.e., similar to you, in that respect), and I once again see no others with that pronounced change in slope.
Your inflection point comes about halfway into the portion of 2020 that has elapsed so far. If I look at your plot of reputation changes per day for 2020, I see that you started getting a higher density of upvotes around the beginning of April.
If I look though the individual posts associated with those upvotes, they are mostly all unique. That suggests someone has started systematically reading your old posts and upvoting many of them. Since you have a finite number of posts, this phenomenon won't last forever, but enjoy it while it does.