BTC Core no nodes

I appreciate this has been asked to high heaven,, at least it was a few years back, but;

Why does my node not connect to peers, and when it finally does they send a few mb?

I initially download about 7% in an hour, then, peers just stopped sending data. I disconnected from them, tried a restart, dbcache up to 4000, maxconnections up to 1000, copied to another computer same issue. At that point I tried VPN as I thought I might be being blocked (I live in a country where they do this...), I get a few peers, but nothing like that first hour. I even tried downloading from work as a tester.

I'm mainly using an M1 Mac Air with an external HDD.

I also tried manually adding nodes (from various places), but this didn't really help.

Any ideas on something I can try?