GCP's max instance count is helpful to a certain extent, but this doesn't completely protect you unless from DDOS attacks. If you have 3 nodes that can all handle 1000 requests per second, and those requests are doing something expensive the max instance limit doesn't help you.
Although I guess if you have 3 nodes that can only handle 100 requests each the damage of a DDOS would be much more limited.
Although I guess if you have 3 nodes that can only handle 100 requests each the damage of a DDOS would be much more limited.