the awkward questions are going to be of the form ‘what the fuck did you think was going to happen’?
What makes you think that all the people who didn't vote not support him for President? There's polling that shows the opposite, that his margins would increase if the turnout was higher.
If you're talking about the popular vote, only the people who vote matter. I'm sure there are people who didn't vote for Trump but who support him. Certainly a lot of leftists and erstwhile Democrats stayed home or voted third party because they were disillusioned with Kamala Harris, which implicitly supports whatever the status quo winds up being.
You can find polling that supports just about any narrative you like, but I don't think you can find much objective evidence that a significant majority of the American population supports Trump but most just didn't care enough to show up to the polls. Votes are the only objective data showing intent that we have, and they don't seem to indicate a sweeping mandate on Trump's behalf.
By definition, if they supported him, they would have voted for him. That's what voting is for.