I agree about posting facts. You won't change anyone in an echo chamber of their own beliefs. That's not limited to just politics.
But whilst those who are tribally loyal to their beliefs won't be our shades there will be people reading who aren't party to facts or opinions from the other side or haven't yet made up their minds. These people can be saved may be responsive to alternative viewpoint and may make their mind up in agreement with you.
I love quoting facts at my Tory loving friend. She's totally dedicated to them.
But she still can't come up with anything beyond "but Boris got the vaccines done" to which I reply "yes, 4 years ago - what have they done since"
Quite a number of times she's actually ended up admitting their cock ups and she has no evidence Labour will be worse nor does history indicate they'll be worse than what this current lot have done.