I’m suspicious that a lot of the apparent inherent benefit of a prime lens is that it can’t zoom, which forces the person holding it to think a little bit more about composition.

It would be an amusing experiment to compare a prime lens to a zoom lens that it somehow fixed to the same focal length. Maybe level the playing field a little bit by applying distortion correction to both lenses.

There's measurements to support your feeling that primes are better than zooms: https://www.lensrentals.com/blog/2019/11/stopping-down-some-... and https://www.lensrentals.com/blog/2017/02/things-you-didnt-wa...

There’s a lot more to it, but I attribute a lot of ‘better in some way’ to microcontrast followed by how the lens handles the transition to out of focus detail.

Yeah, back when I had a Canon my only lens was a wide angle prime. I really like that Sony 90mm prime, DxO says it is Sony's best lens and I think it is.

Ever since I started shooting sports indoors (often w/ that 90mm prime or a 135mm prime) and started to depend on noise reduction I process everything with DxO and tend to use a lot of sharpening and color grading. One day I went out with the kit lens by accident and set the aperture really small and developed the "Monkey Run Style" for hyperrealistic landscapes that look like they were shot with a weird Soviet camera.

The lens I walk around with the most and usually photograph runners with is the Tamron 28-200 which is super-versatile for events and just walking around, I used it for the last two albums here

https://www.yogile.com/537458/all

but for the Forest Frolic I used my 16-35mm Zeiss but it was tough because it was raining heavily -- I was lucky to have another volunteer who held an umbrella for me, but I couldn't lean in. The last one (Thom B) was not color graded because I'd had some bad experiences color grading sports when I got the color of the jersey wrong but now I use color grades that are less strong -- at Trackapalooza the greens just came out too strident and I had to bring them down.

To give you some idea of how powerful noise reduction is, this shot

https://bsky.app/profile/up-8.bsky.social/post/3lv32zudu2c2d

was done in ISO 80,000 with that Tamron -- I wouldn't say it looks perfectly natural for a picture of cat that was not standing still in a room in a basement that is amazing.

All your points are true, but primes tend to have more character as well. I’m no optical engineer so I can’t speak as to why, but it seems like they have more choices on prime design than they do on zooms.