The Microsoft co-founder and philanthropist is taking a break from the future to examine his past — and mulling where the billionaires now fit in.

Other potential buyers include the philanthropist Frank Mccourt ’s Project Liberty, which is raising capital to make a bid for TikTok in order to “rearchitect the platform” and protect user data.

The billionaire and his Silicon Valley associates landed in the capital and immediately moved to cut the size of the federal ...