He can, as long as he stays within the laws.
However, this makes him look bad, given he repeatedly claimed that the Twitter takeover was to make Twitter more pro free speech. Examples:
Two months ago he tweeted (https://twitter.com/elonmusk/status/1586059953311137792):
“Twitter will be forming a content moderation council with widely diverse viewpoints.
No major content decisions or account reinstatements will happen before that council convenes“
Five weeks ago he tweeted (https://twitter.com/elonmusk/status/1589414958508691456):
“My commitment to free speech extends even to not banning the account following my plane, even though that is a direct personal safety risk“
And yes, people can change their opinion, but this seems more like Twitter will be in favor of free speech, as long as Elon likes it.