Though lower-res cameras (4-6-10-12 MP) made me a lot of $$$ though the years and many of the files from those cameras continue to my income, it's just so nice to work with a high-res capture (24-36-45+ MP) and make even a small print!
A decade ago, those lower-res files purchased the higher res cameras I use today, though mostly I've backed down to a "safe-and-sane" 24 MP for most of my work today. It's a matter of balance between ultimate resolution and having to work with tighter craft, or simply backing off a little and being a little more spontaneous and fluid.
Most of the work I produced on my first trip in nearly two years a month ago was "downgraded" even more, to an iPhone with 12 MP and enjoying myself. However, having a large-format printer to first do large, 24x30 "proof sheets" then picking some to then print on larger paper is still quite amazing to me after years of working in a small darkroom and producing small, well-crafted prints on 8x10 and 11x14. Small prints on 8.5x11 are still quite satisfying for one's lap, but it's nice to do a 24x30 or even a 30x40 or 40x60 print occasionally to hang on my wall, or better yet, deliver to a client to hang on their wall and having 100% control from the snap of the shutter.
A man I mentor will soon turn 80. Three years ago he wanted to upgrade his D300 and printing 6x9 inch images on 8.5x11 paper. He put in his time and took some high-end classes and retained the training and then put his time, effort and money into his passion. He's never looked back and now keeps pushing his craft compared to our peers...
I recommended that he just "upgrade" to a D7100/D500. But he wanted the best and went with the 45MP D850 and several full-frame lenses. Two years ago while visit France, he lusted after a wider-angle lens he seldom shot wide before the trip and found out a 20mm wasn't quite wide enough for him...
What he did when he got home was to buy a Z 7 and 14-30mm, 24-70 and the adapter for his longer lenses. But in the mean time, he's now printing larger, 10x15 inch prints in addition to his 6x9 prints and occasionally even a larger print or two. He's pushing his vision and his craft, loving what he's doing and keeps the ball rolling.
Though a lot of what he is doing could be done with lower resolution and an iPhone (which he also has), he's doing well and has lots of room to grow.
Luckily for us, we have good choice today, cameras made in the last decade or so, even lower-res cameras, are totally fine and with good craft are capable of quite remarkable and large prints, even though the math doesn't always support the rules, those rules are meant to be broken!
I purchase my first large-format printer almost 20 years ago and kept getting bigger and bigger printers until I ran out of room. It wasn't just being able to print a larger photo, it was about lower costs for paper and ink and the capability to work pragmatically and practically. Yesterday, my 44 inch printer was used to print 13x19 paper. A few days ago, it was 8x10. Last week, it was 24x30+ gang (proof) sheets. In between, I ran two 24x48 canvas panels to be mounted for a client.
Having large and well-crafted files is part of the joy working in photography and though smaller files are faster to download, edit, process and archive, it's just so nice to have a higher resolution files to start the process, even if print smaller, since they are simply such gorgeous and full of detail that my earlier work (including film from the previous century) simply lacked.
It's all part of finding your niche and if all you are doing is posting small jewels on FB/Instagram, then an Android or iPhone is probably all you need, but for many, that high res image, 24, 36, 45, 60, 100... MP is nirvana and fits them better.