That's exactly what it is. They are using totally fake news CNN and Washington Post to do a totally fake “fact check”.
You may want to look at the election fraud report from the bipartisan commission headed by Jimmy Carter and James Baker from 2005. They agree with what President Trump said.
Nobody stopped him from saying whatever he wants.
Except they have. Just last year, they suspended the Mitch McConnel Senate reelection campaign twitter account. And they recently suspended the Twitter account of Ilhan Omar's GOP opponent.
Back in 2018, they suspended the accounts of several GOP congressmen who were kicking butt on the House Judicial Committee.
“Just last year, they suspended the Mitch McConnel Senate reelection campaign twitter account.”
Twitter is not the only microphone in town. By far.