Anecdotally, one of the reasons that your dock may be dropping out is that it’s Ethernet is probably connected via the USB bus instead of PCIe, which apparently makes a difference because Apple’s Ethernet over PCIe drivers are much better/less generic than it’s Ethernet over USB ones. Plus, CPU usage is much lower with Ethernet over PCIe.
Unfortunately, not many good options to get Ethernet over PCIe. The cheapest is Apple’s own Thunderbolt 2 to Ethernet adapter, and if you need to plug that into a T4/USB-C port, it’s another $69 for that adapter.
Whether your dock connects its Ethernet interfaces over PCIe is a bit of a crapshoot, but there’s a list of docks with confirmed Ethernet over PCIe. Generally, USB-C docks that don’t specifically list Thunderbolt support are all over the USB bus.
Looks like OWC docks are Ethernet over USB:
Dunno how much of this works out in practice vs theory, it may be one of those things that only nerds care about, but there certainly seems to be enough evidence to suggest Ethernet over PCIe/Thunderbolt > Ethernet over USB.