What incentive alignment? In my country the publicly founded TV that I'm obligated to pay for each month is completely biased.
Tax founded/public != real/useful.
Also: I am NOT a "customer": since it's tax founded I am EXTORTED to pay for it.
A customer is someone who has the option to CEASE buying it. I do not have that option.
In my country public TV is decent with good programming and neutral political tone.
When we speak of dominant social networks today however they are runaway adtech cesspools, outright owned by malicious actors, or a combination thereof. That recurring "good stuff becomes shit stuff when getting popular" effect that people lament so much is in no small part caused by adverse profit seeking incentives. There is no dopamine, addiction and hence money in keeping your timeline chill, unpolarized, attached to median human reality rather than freak circus and not riling you up with ragebait.
And naturally anything created by man can be undone and subverted and it can be done to public media as well. This risk however does not outweigh a demonstrably pathetic status quo of the fiery pits of existing social media platforms.