You are an employee and you are overloaded (like the OP). You are worried about getting fired if you don't do enough. Your manager had talked to you about not overworking and said you should not work more than 40 hours. At the same time, the manager said that the company needs only high performers, so you should be working faster. You can't do this, you are already working as fast as you can.

Option 1: you do as told and leave home at 5pm. You spend 40 hours per week exactly, but work is not getting done, so people are complaining about your performance. Your manager is putting more pressure on you, you are worried about getting fired.

Option 2: you record 40 hours per week, but actually work for 80. Sure your home life suffers but at least the manager is off your back. You are getting compliments about performance and vague promises about raise sometimes in the future maybe.

Which option do you think people will choose?

Therefore, we should not have a legal basis for overtime? That's insupportable.

Give people who want it a legal foundation for getting paid for the work they do and people who find themselves in the situation you describe can chart their own path out.

If you want to fudge numbers and be complicit in your own exploitation, you do you. But please, don't undermine everyone else's legal infrastructure to get paid for the work they do.