The oversight board at Facebook (FB) will decide in the coming weeks whether former President Donald Trump should regain access to the platform or face a permanent ban.

Billionaire philanthropist Bill Gates — whom Facebook CEO Mark Zuckerberg considers a mentor — on Wednesday weighed in on the impending decision, telling Yahoo Finance that a permanent ban of Trump "would be a shame" and would amount to an "extreme measure."

He warned that such a move would cause "polarization" if users with different political views divide up among various social networks.

"I don't think banning somebody who actually did get a fair number of votes — well less than a majority — but I don't think having him off forever would be that good," says Gates, referring to Trump, whose Facebook account has more than 35 million followers.

Facebook indefinitely suspended Trump's accounts on Facebook and Instagram on Jan. 7, the day after Trump supporters attacked the Capitol. Twitter (TWTR) permanently banned Trump on Jan. 8.

'An extreme measure'

Gates pointed to the more moderate approach taken by Facebook before the suspension, in which the company labeled problematic posts; and he noted that Trump's future speech may not require dramatic action since his words could carry less impact as an ex-president.

[See also: Facebook allowing Trump back would be 'terrible mistake': Laurence Tribe]

"If he's spreading lies about the integrity of the election, does that need to be labeled? Is he actually less important in terms of causing trouble in the future than he was in the past?" says Gates, former Microsoft (MSFT) CEO and author of a new book entitled, "How to Avoid a Climate Disaster.”

"But it'd be kind of a shame if they have to use such an extreme measure," he adds.

Gates, who avoids political endorsements, has sharply criticized Trump's handling of the coronavirus response and his decision last April to halt funding of the World Health Organization. The most notable run-in between Gates and Washington D.C. came in 1998, when he rejected the need for regulation of the software industry in testimony before the Senate.

The question of whether Facebook should permanently ban Trump has drawn intense interest, garnering 9,000 comments during a public comment period. Proponents of a permanent ban include former first lady Michelle Obama and former Facebook security chief Alex Stamos; while skeptics of the potential move include German Chancellor Angela Merkel.

Facebook sent the decision last month to its newly formed oversight board, a panel of judges made up of experts and public figures from around the globe. The board was given 90 days to decide on the ban.

The oversight board will distance Zuckerberg from content moderation choices made by the company, Gates said, acknowledging that he'd once suggested the idea of such a board to Zuckerberg.

"Get it out of, 'Okay, this is what Mark thinks' — rather, these are some eminent thinkers and in each country, they may reflect the cultural values of that country," Gates says. "So you're bringing them in with a sense of responsibility there."

If Facebook does ban Trump, it may drive his supporters to other social media sites, fracturing online debate among groups of people who share similar political stances, Gates said.

"There are people who want to see debates around [Trump's] views," Gates says. "Splitting the digital world into, OK, here's this site that's for one party or part of one party, and here's another one — that kind of polarization is probably not a good thing."

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