Reciprocal action gives the enemy plenty of reason to escalate.
If else, Russians see any restraint by the enemy as a sign of weakness and an excuse to escalate even more.
“You probe with bayonets: if you find mush, you push. If you find steel, you withdraw” ― Vladimir Ilich Lenin
It may give them pretext
But when they want to escalate, any convenient pretext they can fabricate will be spewed out
Appeasement ONLY encourages aggressors. They can ignore any statements and rhetoric and correctly conclude: "I did X, no real consequences, therefore I can do more X".
The ONLY language they understand is force or consequences with real cost to them. Vladimir Lenin said it very clearly:
>>"We probe with bayonets. Where we find steel we withdraw, where we find mush we press on."
When delaying reciprocal action, the cost for the next round ALWAYS increases.
Delaying response is a fools' game.
Democracies always play that fools' game because for any one politician, it is easier to kick the can down the road with bad reasoning like you posted.
But when the situation finally becomes unavoidable, it is a deep serious problem. Here we are.
It's really just the Imperialist Autocrats' standard playbook, and it is little different from the schoolyard bully — "What's mine is mine, and what's yours is up for grabs".
They all just keep aggressing until they get hurt, then they find someone else to harass and steal from.
What’s the answer?
The key is that the measure must cost the aggressor more than they gain, and of course be reasonably proportional.
Plus, even if we stick to your irrelevant requirement, response is better. It is less bad to have no subsea cabling for everyone vs making no response and ending up with only the aggressors having subsea cabling.
But of course you can't /know/ the outcome beforehand, which is what makes it a high-stakes game. The only thing you know is that if you keep doing nothing they'll have no reason to stop.