It is starting to sound like it might be this issue: For users encountering NET::ERR_CERT_DATE_INVALID Error
In which case yes, it is more or less a Windows 7 issue at heart, but there is a workaround there.
I should add, that if your system meets the requirements for Windows 10, you might still be able to get a free upgrade. Worth looking into. Otherwise yeah, a move to Win 10 (or 11) with a new system may be worth it for many reasons if you can afford it.