Agreed. I spend time on it and am inefficient but it's overall worth while taking into account the benefits. There are many critical or difficult things I wouldn't automate myself but my goal is to reduce my requirements down to substitutable services where my counterparty doesn't have a monopoly over me.
I'm a freelancer, and make my own documentation supported by invoices/receipts etc. As an employee, yeah, it doesn't make sense to self-report when the government already has the information it needs. A lot of countries use withholding so only send a statement of what you've paid and somewhere to complain when it's wrong, like you suggest.
I think some change is coming wrt technology. There seems to be more interest again in open source.