Troubleshooting New Windows 11 NUC PC network connectivity issues

I recently added a new Windows 11 NUC PC to my home Wi-Fi network and its connection to the rest of the network is inconsistent.
In short, sometimes it is reachable from another Windows 11 PC, two Android TV boxes and an Android phone. Sometimes it works, sometimes it does not. Sometimes it works for one app (like Kodi) and not another (like VLC). Sometimes the reverse. I can connect to it over RDP but using Explorer I can't reach it even though its name is listed in the Networks tab. The network is stable for and between the other devices.

It is a rather chaotic performance and I'd appreciate some help wrangling it.

I switched profiles from Public to Private, and turned the features on in Network & internet \ Advanced network settings \ Advanced sharing settings. Everything back to normal.
I'm pretty sure I did so before, but perhaps the Public profile has more aggressive restrictions. Then again, I may have simply forgotten to do the most basic of steps. Kind of amazing.

SECONDS LATER:
Whoops. Spoke too soon. Seems to work for the PC and the Android phone, but while Kodi works on the Android TV, VLC is once again stuck in Loading... So, not a complete success. Note that I never had issues with VLC when I had another PC set up as the media server.

A WHILE LATER:
All other apps seem to work as intended. The trouble with VLC on Android TV (getting stuck on the loading page when attempting to reach the PC share on the network) may be a VLC issue. I will update with details if I learn anything definite-ish.