I find this strange to believe. Every big company has levels, unless your existing L7+ IC is below market, you can just pull L7+ salaried ML engineers with some secret signing bonus like literally everyone else.
Culturally, none of these companies were happy to pay anyone except the tip, top "distinguished" engineers more than 300K. AMD seems to be stuck in this mentality, just as IBM is.
And that's why creative destruction is essential for technological progress. It's common for organizations to get stuck in stable-but-suboptimal social equilibria: everyone knows there's a problem but nobody can fix it. The only way out is to make a new organization and let the old one die.