Alright I tried it earlier today, it's VERY good.
There's also a bunch of extra options to adjust the amount of Bloom and so on in the graphics settings (among the usual DOOM options). I only played the first 3 maps but yeah, it's very good. It helps a lot with the atmosphere, and seeing light reflections on floor tiles on original DOOM assets is quite the gaming moment for me lol. At this point, bring RTX effects to Duke Nukem 3D and we're set, really (of course, argument is 'why not just doing this to all oldschool / early 3D or semi-3D games' and I agree but we all know it won't happen for the majority of the games we'd wish to see that happen for).
Note, however, that the 'regular' DOOM is still just fine to my eyes. It's easy for me to say this though, since I pretty much started exploring 'PC gaming' with DOOM. So firing up DOS DOOM, up to GzDOOM variations with mods or whatever, I don't mind. It's DOOM, it still kicks ass to this day; ray-tracing or not, doesn't matter in the end.
BUT... it's fun and pretty to see our good 'ol DOOM with these new visual effects. It's not the end of the world, really. It's just 'physics-accurate' lightning. To be honest if back in 1993 we happened to have hardware to produce this same sort of lightning in video games chances are it would have been part of the then-gaming-industry standards and id Software would have implemented it in anyway. To me it's a bit like saying that not all games should be open world but open world gaming only arrived progressively and 'naturally' as the hardware and memory storage improved, so games got bigger (even though the very concept of 'going any direction as you please' even in a 2D game existed for a while; just taking the original NES Legend of Zelda as an example speaks for itself).
Point is, it was bound to happen, basically. Be it now 'because why not', or back then because back then it would have been part of the industry and possible in the 90s; it would have happened back then anyway. So anyways, I digress a little here but the MAIN point is: Hey, this is fun, it's DOOM, and these new visual effects are actually contributing to the game's atmosphere, really like it.