Riiiight... And what Foundry will they be using? None are anywhere near even limited production status @ 7nm. Yes Samsung and GF are doing "tape out' for engineering testing of the layouts but that has little to do with being anywhere close to a viable production status.
Do you know this from some source at the foundries or do you just repeat somebody's baseless speculation? Edit: Wasn't that QuintLeo who convinced you that Intel isn't offering foundry services? End edit.
It would seem that Bitcoin mining IC is near perfect test product for a new process: it is repetitive, it tolerates bad yield, it is free of actual trade secrets or intellectual property in its circuitry. It would be beneficial for both foundry and designers to cooperate and profitably sell the wafers fabricated during process bring-up.
GMO being Japanese could have an additional benefit of really being able to sign binding non-disclosure agreements, unlike the mainland Chinese.
I would love to hear from somebody who has current experience. Mine is really dated, but even a very small fab-less company had been trusted with internal fabrication process metrics provided that they made actual technological and legal effort to protect the trade secrets of the fab.