PtP should be correct, but it is possible that as wireguard is a new thing, it has broken multicast handling. Generally, PtP tunnels should have no problems to use multicast - just send everything to the other side. But as the tcpdump on one side shows periodic hellos from both sides, then it is unlikely to be an issue.
The dumps I've pasted were on both gws and I don't really see it going through, I only saw the broadcast but never any kind of answer to it or coming out on the other side, so there still might be an issue.
Also i saw that your config files do not have 'log' option, so you have no logging. You should enable logging and see if there are no error messages.
I didn't paste the log options from the conf, they're at the top, but you're right, I should have enabled debugging as well to get a better view.
Although unrelated, i would suggest to remove these OSPF options;
tick 2; rfc1583compat yes;
Care to elaborate why? I do trust that you will know better.