I have noticed that!
Yes, diversity is good including diversity in machine control software.
Marlin doesn’t serve the Web UI directly, it mostly is used with either Marlin mode (12864 LCDs), BTT TFT mode (where the TFT acts as its own UI and sender), or if you add an ESP-01S you can get a cousin of a similar Web UI to what FluidNC uses on ESP-32s (same original author).
If you want to run that kind of setup and have an SKR Pro 1.2 or other supported BTT board, there’s a full thread here on the forums about this. Ryan used to sell a fully loaded ESP-01S for use on the SKRs here in the shop.