But the problem began decades ago when sysadmins started using firewalls to control what employees could access. During early 2000's I was involved in moving a lot of apps that used a bespoke port to port 80/443 just to make sure our apps and services didn't have any client hiccups due to (rightly so?) belligerent sysadmins.
All this has really done has made sysadmins lives harder bc of packet inspection. So, all app developers and now infrastructure solution devs must run thru 443, otherwise the take up wouldn't happen. The internet is effectively running on one port nowadays.