The story for years is that Apple doesn't need to make a computer that you can expand on… because USB! Why not give you six, eight or ten USB C ports? For those who want to keep the back of their computer neat (OK…) you can just plug in your one USB cable to your dock or hub. Will adding more ports affect that? I have a hub, and I have a bunch of crap plugged into it that I don't need on a daily basis. I keep them plugged in so that they're ready when I need them. On top of that, a few things that I prefer to plug directly into my computer because they work better this way.
As Apple knows, people aren't upgrading their computers as often anymore. If I upgrade from my 2013 iMac there are things that I'll have to replace. I have speakers that plug in with a Toslink connector; Apple had to get rid of that port because "thin", so I'll have to get a USB adapter for my speakers. I get why they got rid of the SD card slot, but wouldn't a USB port on the side be nice for the times that you have to temporarily plug something in like a flash drive or an external hard drive?
It wouldn't be so bad if there was a Thunderbolt 4 dock made for an iMac. On the back; ten USB A ports, a combo headphone jack/Toslink connector, HDMI port. On the front; USB A and USB C ports, SD card slot, headphone jack. Have an internal bay (or two) for SSD drive expansion. Ditch the laptop specific stuff like the ethernet and VGA ports that many docks have. In fact, forget the extra ports on the iMac- somebody make this dock for me!