It definitely makes it more difficult to switch endpoints manually. I have multiple VPN connections with different exit nodes configured for failover in case one (or more) of them is unreachable. I don’t run into geoblocking issues very often but I also don’t route all my WAN traffic over VPN. Just some of it.

What you can automate depends on your routers capabilities. Mine is a Mikrotik which does have fairly extensive support for custom scripts. However, detecting Geoblocking is probably going to involve parsing HTTP responses which is beyond the capabilities of almost all consumer grade routers. You would have to effectively do a MITM attack (aka deep packet inspection) in order to accomplish that on something other than the client device.

TLDR: I manually change routes to a different VPN if needed but I very rarely run into Geoblocking issues.