Given how much time I spent on my first real multi-tenant project, dealing with the consequences of architecture decisions meant to prevent these sorts of issues, I can see clearly the temptation to avoid dealing with them.

But what we do when things are easy is not who we are. That's a fiction. It's how we show up when we are in the shit that matters. It's discipline that tells you to voluntarily go into all of the multi-tenant mitigations instead of waiting for your boss to notice and move the goalposts you should have moved on your own.