The latest update has exceeded my computer specs - I have windows 7 - can I backdate it?

What update, exactly, did you install? My Win7 system was never offered anything beyond version 15...

Way past time to move on. You should be able to update to Win10 with nothing but beneficial results.

My strong opinion - there is no reason to stay with WIN7/XP if you want to use it latest Adobe Software as subscription. Check your purse for the futire upgrade of OS and hardware. 

Even if your old PC works with some scanner/plotter/RIP/other machine your are need new PC. Stay away this old PC with old hardware only for their old tasks without Adobe CC. 

(Link modified by the Moderator ^VS)

As far as I can remember InDesign 2020 was the last version compatible with Windows 7 and is no longer available for download. Adobe only makes InDesign 2021 and 2022 available for download and install.

Microsoft stopped supporting Windows 7 quite some time ago. It's time to move on.

With the Creative Cloud app, you can go one version back (and uninstall your current version). What version are you looking to install?