I think it is because most of those things are just regular sysadmin things and homelab more refers to setting up hardware or software that you wouldn’t normall

I think it is because most of those things are just regular sysadmin things and homelab more refers to setting up hardware or software that you wouldn’t normally find at work. As for your actual problem, a lot of ports are blocked by ISPs because a LOT of computer worms have used them to spread malware in the past. However you usually can test to see if the port is open as well as try alternative uncommon ports like 47364 to see if they work. Some ISPs, although I believe mostly mobile ones, also use something called CGNAT where your Internet IP is actually an internal network IP within a part of the ISP, and you can usually test for this by checking if your IP is in a private range.