Roland, I suspect that a prime 200/2.0 could be obsolete.
Not made any more is not quite the same as obsolete. The existing lenses continue to be in use.
I think the most popular filed for the lens is opt for a 70-200/2.8 lens thanks to the advanced AF and high-ISO capability of modern bodies, mirrorless or DSLR.
Yes, but that's exactly the problem, the images look exactly like everyone else's. Millions of 70-200/2.8 have been made. Only thousands of 200/2's, which puts its users in a position to distinguish their images from the masses. What is killing interest in photography is that everyone has seen the same things over and over again. Having a rare lens can in this case give an advantage of a different look.
The workhorse prime for this area should be 400/2.8 and 600/4.0 now, as Sony's lineup suggests.
400 mm is too long for my uses, let alone 600 mm. Even 300/2.8 is about the longest I could practically use at events or figure skating. The 200/2 is much more practical in my opinion and gives a 1 stop advantage. The 70-200/2.8 works for a lot of things giving good results but gives no advantage over millions of other photographers shooting with the exact same gear. If there is no difference then there is no point in being there in the first place to make photos as they will be made regardless of one's presence. (Note that I'm not saying there are not other ways to distinguish one's work - there are, e.g., lighting styles, but in many situations one is limited to the light that is available). The 70-200 from first row shows the ads in their full glory, which is an issue, and the bokeh is okay but not spectacularly beautiful. The 200/2 when filling the frame or close to, does make them less easier to read while making the audience an interesting pattern of blurred colour blobs. With 300/2.8 it's hard to fit the subject in the frame except at the far end of the rink. Some are using 400/2.8 from the long end but those photos isolate the skater with basically no surroundings, which makes the images lifeless to me.
Sony likely chose 400 and 600 to make as they didn't have a foothold in the sports market and so they had to start somewhere, make the fewest number of long lenses they could to cover these applications. This doesn't mean a 300/2.8 is obsolete. It just means that the new standard was made by a company with no previous presence in the market it tries to get to, and does so making basic errors. Of course the 400 and 600 are big and easy to spot and maybe that's why they wanted to make them. Nikon made a 120-300/2.8 which in my opinion shows a much better understanding of what is needed for sports, but it's just outside of my price range and doesn't follow the current trends for lighter weight. Maybe I should have gotten it regardless but I'm used to shooting sports hand-held and 120-300 would put me squarely on a monopod and with a substantially longer lens (physically) it would seem a bit too clumsy for me. In some ways very practical (the focal range) so it's not a clear error from either side but my preference would have been FL versions of the 200/2 and 300/2.8. I like an emphasis on out-of-focus rendering with good sharpness and am not convinced I like the new ultra-sharp, high-contrast look.
Sony's approach to long lenses has been successful as the sports photography market has been dwindling (both before and due to the pandemic) and wildlife photography is booming (as people have had time to spend in the outdoors due to not being able to spend time with other people). The Sony teles seem to have been very well taken by wildlife photographers. I still haven't seen any A9 or A1 series cameras at sports events.
But eventually sports and events will return and the need for something in between 70-200 and 400/2.8. The assumption that it's okay that a lens should cost 11k€ or more is just out of this world. I guess this is what focusing on the "high end" means? Yet Nikon have success in the intermediate products such as the PF lenses, the Z6 II, and the Zfc. I don't mind if Nikon don't make a 200/2 if they make other primes (a bit smaller aperture or slightly different focal length) with similar rendering. I'm not hung up on the specs. I just notice in the Z lineup there is no fast prime longer than 85 mm and shorter than 400mm f/2.8. This gives me pause as to the suitability of the brand to what I want to do, as this range is exactly where I make most of my photos and prefer the primes for the "look" of the images is more subtle.