His arguments aren't even that great. Most artists I worked with take payment by artwork, not by the hour, if you hire them as freelancers. They give you a rough estimate of final costs when you tell them what you want. And they're willing to make changes until you're satisfied. You're not going to pay 50 dollars more just because you needed to make a few adjustments to the artwork. Most artists for hire are reasonable people. Maybe he's just doing it wrong and giving them temporary contracts where they're paid by the hour rather than commissioning assets and paying for the finished artwork, but why the fuck would he do that?? You only do that if you make the artist a permanent or semi-permanent member of the team and he obviously doesn't want to do that.
Same with his habit of browsing free game asset sites. Why doesn't he just browse the Unity and Unreal asset stores? There are tons of decent to good looking 3D assets there that are cheap and can be converted to good-looking 2D sprites for a fantasy game. Plenty of good-looking castle walls and medieval objects, for example. There are packs of a dozen medieval household objects for 10 bucks. Buy one of these, take screenshots of the objects from the right angle and edit them in photoshop just a little bit, and boom, you have objects that look 1000 times better than the puke-colored stuff that litters most of Vogel's games. Assets like those are cheap as fuck. You don't have to be a penny pincher about this.
And all of this still doesn't explain why he can't spare 200 bucks to hire a composer to write a soundtrack for his games. One of the most lacking things is the lack of music. Yes, some people turn off the music when they play games (lol), but to me it just feels like something's missing when there's no music at all during gameplay. All the indie games manage to have soundtracks. Age of Decadence, Underrail, even fucking Eschalon had a soundtrack (and a beautiful one at that - made by a great Bulgarian composer; maybe Jeff should just hire more eastern Europeans, they're much cheaper than the high prices he quotes). Why can't he afford a soundtrack? Musicians who want to compose for games are a dime a dozen. There's no way it's a matter of not being able to squeeze one into the budget. It's pure laziness and unwillingness to even think about this issue. He obviously doesn't care about having a soundtrack, so why invest any time in looking for affordable composers?
Also he fully ignores the fact that, had he invested the big money he made when he went to Steam into a decent soundtrack and art assets the quality of, say, Shadowrun Returns, or even just Underrail or Project Zomboid, he would now have great assets and a visual style every potential customer will like. People who like RPGs would be drawn towards his games and not put off by how ugly and silent they are.
When I played Spiderweb games for the first time in the late 00s (2008 or 2009 or so, discovered them after joining the Codex), I did enjoy the gameplay and writing, but the graphics looked like liquid puke to me and the lack of a soundtrack made them feel a bit soulless, so I just put on some instrumental music in the background. The presentation is not just bad, it is actively off-putting, and I'm pretty sure that quite a few people who would have enjoyed Spiderweb games gave up on them because of the terrible presentation.
He may not be able to vastly expand his target audience by improving the visuals, but not actively putting off a substantial part of the already extant target audience is also quite nice.