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.