xDS: v1.66.2 and above break most xDS client gRPC requests

[marcel808]

What version of gRPC are you using?

v1.65.0 works, 1.66.2/1.67.0 cause most gRPC xDS based requests to fail with error

rpc error: code = Unavailable desc = xds: error received from xDS stream: EOF

What version of Go are you using (go version)?

1.22.6

What operating system (Linux, Windows, …) and version?

Linux (Google GKE)

What did you do?

We have go service pods that call out to other services using the istio agent (inject.istio.io/templates:a grpc-agent), prefix the service urls with "xds:///" and import _ "google.golang.org/grpc/xds".

istiod-1-22-4

What did you expect to see?

Succesfull gRPC requests load balanced using xDS

What did you see instead?

90% gRPC failure rate with error: rpc error: code = Unavailable desc = xds: error received from xDS stream: EOF