I didn't pay much attention to the new 3D features in Illustrator because I wasn't impressed then and several years later, I'm still not impressed with them now. I'd like to see these built to work how (I assume) most people actually expect them to work, which is as a powerful, vector-based 3D tool to manipulate 2D shapes. I expect the output to be clean, sharp, and vector-first for easy editing. This is something the old tool aimed to do, though quite clunky by today's standards.

Today's 3D tools feels like a tool ripped straight from Photoshop and taped onto Illustrator, which is no good at managing all the raster effects it prioritizes. If I want to create some stylized 3D logo or text or graphics, the new tool will spit out clumsily-shaded, rasterized, and just plain ugly renditions. And I have limited options if I want to clean this up in Illustrator. Outputting to vector feels like an afterthought. The only option is to create wireframes, which is a mess of overlapping lines that almost has me doing the work all over again. With how quaint the old tool was, at least it produced clean, culled results which could be further modified. Because that's what a tool is supposed to do: save me time to create the art I want to make, not make more work for me.

Basically, I don't think this tool is anywhere close to accomplishing what it set out to do or even match the features of the tool it's meant to replace. Existing tools within Illustrator don't quite match the features for the look I'm going for either. Envelope Distort does not account for perspective, leading to an odd look due to lack of foreshortening. Free Distort is hopelessly outdated but could use more control over the foreshortening effect. I may have to consider third-party tools or just abandon this look altogether since it doesn't look like Illustrator is capable of producing this seemingly common look.

It was obvious when the new Substance 3D tools were announced that legacy functionality would be ignored completely.

This is frustrating to us who are trying to use what Adobe itself refers to as "Vector Graphics Software" to create vector graphics. It certainly is very representative of what modern Adobe prioritizes and how haphazardly it implements and then abandons things to rot.

I have the feeling that there are a lot of new features introduced that are not properly finished/polished.

If they ever close the gap — yes.
At the moment proper vectors are not just gap, but a canyon. And I can’t say they are in a rush to close it.
Besides that: no revolve direction control (they are just opposite compared to classic), no fit mapping or decal snapping, no partial presets, no lighting lock... the list is long. They accomplished a lot, but I feel it slowed down recently.

I remember this conversation with a high Adobe employee about the gap between classic and the new 3D:
Ultimately we don't want there to be things that only classic can do. These are super important for us to see as we work to close the gap.
It's such a better and more modern foundation - there is a lot of potential upside here. And it will be a superset of what Classic can do.

Classic 3D hasn’t changed... that’s the problem. It does not not get changed and probably won’t be changed. So instead of trying to fix it, the team seemingly decided to leave it as is and try anew.
So either you are correct with 'something else broke it', or it’s a general notion of 'software becomes worse'. Hard to tell without an actual file you’re struggling with.
Having vector 3D, REAL one, wit ho no raster-trace-over is definitely a thing many users want... they don’t vote though! Soo....

I used classic but that has not helped me produce a clean, easy to use vector. I used Ray tracing but it only created outlines that I cannot easily select and some of the shapes are completely missing. I know this capability existed b/c I’ve used it in the past! No idea what’s changed but it feels like Adobe developers are constantly “fixing” things that aren’t broken… leading to functionality that is broken.

Yes, we need the ability to convert 3D to simple vector art to revise colors and edit as needed! Please add this functionality. I do not see a vector output option. When I try to use "Ray Tracing" the output is too complicated. When converting type to 3D, I need simple access to change the depth portion as a single color and the face portion as a single color so I'm not stuck the with difused output color change.

Thank you for the information, Egor! That's good news.

I use 3D-vectors ALL THE TIME. 3D vectors work seamlessly with vector illustration work, and are vital for good workflow.

3D-raster/bitmap is almost useless. There are countless applications that do that already.
PLEASE PLEASE PLEASE do not abandon 3D-vectors!

Thanks for there concern, Mark! Proper vector expanding is in plans for next builds. It should be better than the current implementation, which you can try in the 3D & Materials panel's menu, by toggling the vector output option.
Not a convenient way, I know.