Old school Zeiss glass is like butter for any camera body. My dad told me to stick with Nikon and spend my money on lenses first. He was not wrong. You can put 25 year old professional lenses on a mid-market Nikon body and the images will be stunning with very little effort.

Oh, tell me about it. Sure, you can only stop-down meter Pentax 645 lenses on F mount since the aperture levers go opposite ways, and I don't know any of the YouTubers who are the only ones left doing that kind of engineering. So what? With anything that doesn't move around a lot, and the sensor crop working in your favor to deliver only from where the glass is sharpest - sure, you're not doing wide angle that way, but where else are you getting a razor-sharp 120mm f/4 macro for a hundred bucks?

The 105mm f/2.8 VR II Micro-Nikkor is still better for the field, of course; that kind of work requires a lens which can talk to my body and flashes, and the stabilizer is actually useful. But for folks not chasing wasps around or the like - and willing to be a little old-fashioned about their working, in a way that will teach you about photography some of what a Piper or Cessna does about flying - there really is no better way to get anywhere near that kind of performance at a similar price point, and a well-maintained lens of such stately age is a joy to work with besides.