https://sw.kovidgoyal.net/kitty/invocation/#cmdoption-kitty-...
In tipical GNOME fashion, they have decided to replace this largely working piece of software with on with one that places solidly at the bottom of the article's list (ptyxis).
If you run:
GSK_RENDERER=cairo ptyxis -s
You can verify that with 69,985 here RES and 52,428 of that SHR. With 5 tabs open it jumped to 71,208 here. Presumably for the encrypted scrollback pre-allocations.
You still may not choose to use it, but it should stay relatively similar the more tabs you open.
Also, it's not a core GNOME app. It's just an app I wrote for me that the distros seem to have liked for its design/platform integration.
Another thing for a very long time has been that most other terminals don't support bitmap fonts. This was/is critical for lower DPI monitors. Today I've mostly made the switch to TTF fonts.
This is similar to the `kitty --singleinstance` mentioned in another comment by amarshall.
edit: the article did mention st but claimed it had no scrollback, that's what the patches are for. st-flexipatch makes it easy to enable or disable the patches via c preprocessor defines.
I think if you can get use to tmux/screen you may like that better :)