SharePoint Classic Templates

Hello community!

So we all know that classic sites need to be converted to modern sites, however, if you have a site that was built on a classic template (but has since been converted to a modern site), do you really need to do anything else?

I could honestly give less of a crap what happens to classic templates, I just want to make sure that my site which was originally built on a classic template isn't in jeopardy.

My knee-jerk reaction is "no" because otherwise there would be thousands upon thousands of sites that likely break.

Thoughts, feelings, and opinions appreciated.  Thanks!