His family owned a crane company which means they were in the construction industry, not exactly the bastion of far-left libtards.
Whenever these events happen the first thing people on all sides try to do is link a political motive. I can just as easily go on Twitter and post that Travis Reinking was a Trump voter who was angry about abortion. It doesn't make it so.
What we do know now is that he had an apartment across the street from Waffle House, where presumably he went to put some clothes on. At some point he had a Facebook account that has now been deleted. By who is not yet known but he did post about the Illuminati conspiracy on it back in 2017.
Was he a far-left liberal? Maybe he was, maybe he wasn't but I'd be wary of claims on social media unless there is substance behind them.