Of course, real-life often is different than theory. Does your machine have a spinning disk or an SSD? I am much faster to enable swap on an SSD, since it won't be painfully slow, should we ever get into a situation where our RAM is saturated.
What happens in cloud VMs? These things use a network disk storage (transparent to us), and often writes need to be sent over the network more than once (for redundancy). How extensive swapping would behave in such an environment?
As for saying no, it's important to set some rules to avoid chaos, but it's also important to trust our senior people to take decisions. If they need to go against a rule, I would expect a good explanation in their commit —because, infrastructure as code— and documentation. If a junior wants to go against a rule, they can consult a senior. Issuing a no and expecting everyone to follow it blindly, is the worst form of micromanagement. :)