The 4070ti would be more a lateral move than an upgrade if anything. If you just really want to get a new card and have around an $800 budget, look at the 7900XT cards. They just came down in price, matching the 4070ti’s, while beating it almost universally in rasterized benchmarks, plus you get 8 GB more vram.
For something like MSFS, the game moves so slow that I don’t see the benefit of frame generation. With frame generation on a slower card, artifacts are more visible. If you are that slow on fps to require frame gen, I don’t think the artifacting is worth the trade-off and would rather reduce graphic/CPU settings. If you get a card that can push enough native frames so artifacts aren’t a problem, you’ll be pushing enough native frames to run the game smooth anyway. MSFS also doesn’t have ray tracing, so you’ll get no benefit there either, even though Nvidia is better at that in general.
But honestly, if you already have a 3080ti, that card was great for its time and still rather good for the sim. If I were planning an upgrade from that, I would want a much larger performance increase, so either the 7900xt, 4080, or 4090. If those aren’t in your budget, I’d hang on to what you have and save up more, or maybe invest in something else. I.e. A better processor if you are main thread limited or want to add extra stuff to the sim. Or maybe some peripherals for better immersion.