Short answer, no. The Trident is capable of more than 25 FPS in Doom (when used with a faster CPU), so you would see no tangible benefit from such an upgrade.
I think the Trident is a good match for a DX2-66, unless you want something fancier, just for thrills 😀

Yeh I don't think its worth upgrading either, no matter what CPU/Video card you have on a 486 Doom will have slowdowns on big levels and Quakes a form of torture.
It's only in benchmarks you'll notice any difference, real world use you may get a couple of frames but hardly the difference between making a game playable or not.

Thanks for the replies, that matches what I was thinking 😀 I want to keep this machine as a DX2-66 so unless there was the possibility for a decent % uplift in performance by getting a better card, it doesn’t seem worth it

The only thing I can think of is getting another card to keep as a spare just in case. But if the trident is filling all your needs you probably won't see any benefits to a better card unless you want to run a higher resolution then a card with more ram would help.