This is the fourth time I'm in the market for a networked color laser printer. Ugh.

Here are my search criteria:
1-A) Refillable toner cartridges. Ideally, this means there are no chips in the cartridges that use a count of pages to say when the toner has run out regardless of how much toner is actually remaining.
1-B) If (A) above is devoid of reality, then lowest cost per actual page of toner cartridge.
2) Low cost per page of replacement imaging cylinder.
3) 100 MB/s wired Ethernet connectivity with an easy-to-set IP address. I don't care about wireless at all.
4) Postscript compatible so I don't have to rely on a proprietary driver that the manufacturer may decide to stop maintaining. I don't want my new printer to quit working just because I update to a new Linux kernel or whatever. By the way, I use Fedora/Mate.
5) Printer must be able to tolerate periods of disuse. I might not print anything for a month or two, then I might print a thousand pages all at once.
6) Decent quality photo printing would be nice.

Thanks in advance for any suggestions, reviews--positive or negative, or horror stories.

any samsung will do

As for #1, they do get their money from the supplies so they aren't interested in making stuff too easy on you. This kind of goes with the last requirement for good photos. You are almost stuck using the matching paper and matching toner/colors to get some results. Many people complain about poor performance when generic supplies are used.

Many printers have the ability to be edited to use other connections. They may not even advertise it, you have to use menu on printer to find or read every manual.

(opps)

Just a couple of observations about printer technology -- laser printers are by their nature tolerant of being off for periods of times then doing large runs though the smaller ones may, I think, have problems with the fuser heat if the runs are very long (running the device for hours). Laser printers are generally bad at photographs -- the nature of the technology means you'll get newspaper-like dotted-coloured-blob images or similar rather than the blended colours of inkjet.
Any networked printer worth its salt ought to speak raw print (port 9100) and LPD/LPR (port 515) so look for that.
Oh, and as to 2 -- for colour you may have up to 4 drums and a transfer belt to worry about so watch out for that.
Then, depending upon how long you expect it to last and how much you are printing, how much you're spending etc. there are many devices with parts which only an engineer can replace that either wear out or a counter says have worn out (in which case you can usually hack around the counter) that may cause you problems. These are worth googling for and, of course, waiting for more replies here.

I have an Oki C5750 which I believe meets all your criteria, except perhaps no. 6, depending on your definition of "decent" photo prints.

Don't know if this model is still being sold - I got mine several years ago at a nice price. It is a table top rather big thing which can do some heavy lifting and also sit idle for months without turning sour. Highly recommended.

Thanks for your suggestions.

After two solid days of research, I chose the Ricoh SP C320dn. It's more of a small office printer than a home oriented printer, but:

1-B) It has the lowest cost per actual page of Ricoh branded toner cartridge. Black is 1.6 cents per page. Color is 9.3 cents per page, and that includes the initial purchase price spread over the expected life of the replacement imaging cylinder. The fact that the cartridges have an expected life of 6,000 pages is really nice. Of course, these 6,000 pages represent a mere 5% coverage, so the page counts may be highly inflated. As long as everyone holds to the same standard, the actual output should be relative.
2) The replacement imaging cylinder has an expected life of 90,000 copies and then it can be replaced. Most others were in the 15,000 range.
3) 100 MB/s wired Ethernet connectivity--check.
4) Postscript 3 compatible--check.
5) Printer must be able to tolerate periods of disuse. Well, let's hope, anyway.
6) Decent quality photo printing may be a bit too much to ask for. The colors on the photos I've printed so far have been too rich. I think I can deal with it.