(I'm saying this with my CMU hat, not my Google hat.)
The era of the mainframe, with each provider competing with a custom chip, wasn't necessarily beneficial for individual buying computer power.
If you look at processors, you see that with the early custom processors, followed by some standardization and copy around the IBM S/360, followed by more proprietary innovation around the PC era, resulting finally in the x86, eventually disrupted by the mobile chips, which then consolidated around ARM and so on.
With cloud computing, we are essentially going back to the era of time-shared mainframes with remote access.
The (expensive) report from The Information upon which that article was based speculates a little more about chips for training.