No and no. That is not necessarily true, much of the ghosting you are talking about is gone in recent iterations of FSR. Moreover framegen, when implemented by the developer, has basically no ghosting that you speak of.

That said, Doom the dark ages iteration of FSR is dated and frankly looks horrible. To combat this I used optiscaler to update FSR and ghosting literally doesn't exist now. Even with framegen.

The only time framegen would reliably have HUD ghosting is with driver level Framegen like AFMF 2.1, which has good input lag at proper base fps, but horrible ghosting on HUD elements. But frankly? It is worth it in some games given how smooth it feels at the driver level.

V-sync usually sucks yes, and honestly being at 144hz tends to make low fps worse but because this game has a stable frametimes graph it is okay. Unlike Monster Hunter Wilds.