The first proposal of having a minimum corporate tax rate probably doesn't mean a lot because you to then start policing what subsidies governments give to effectively discount below 15%.

The more interesting part is what I hope is the start of serious efforts to tackle profit-shifting, which is a name invented for "transfer pricing" because that is technically illegal. But it's the same thing.

A good starting point is that if you book x% of your revenue in country A then country A should get to tax x% of your profit.

Here's another part of this they should adopt: borrowing money should count as repatriating profits. In the era of zero interest rates debt is used to effectively defer taxes forever. There's no legitimate reason to allow entities to borrow money at near-zero interest rates instead of repatriating retained earnings.