Glad you can if you wanted to. I see a number of people without that ability trying to put through stuff they did not make. Especially those using Blender, since it is free. In truth, they just installed Blender & are hanging on for dear life.
I have found though, that you almost never need to make your own stuff, other than rooms & larger stuff. There are absolutely great specimens in abundance. They are made by people who consider it “done” a little early for real time situations, but getting them ready is a lot easier than what it took to get them as far as they got.
Some are really old, but those ones can really clean up far better than expected, when you change to a material friendly to PBR.
These modelers, I think, are using extra vertices sometimes just for aids in modeling, & also do not care how many vertices it takes. Maybe they see it as a badge of pride to have massive #'s of verts. They even make things which are completely inside something else, & cannot even be seen. They may also see themselves as documentors, or something.
The skills to do a little touch up, reduce vertices, & swap out for PBR materials are probably even more important than knowing ALL the things you need to know to make something that does not look like crap.