It will affect Microsoft, NVidia, Oracle at least and many other companies which have deals with them.

And when it does, the losses in their 401Ks will be due to the artificial gains they've been seeing in the last few years.

IOW, I don't expect people's 401K to dip below what it would have been had the AI bubble never existed.

It depends how big is the panic. It could take down many companies.