Imagine syncing and validating a 3 TB blockchain from scratch. Do I need to run my nodes only on top end Xeon machines? There was some discussions about a 'drastic' future in which new nodes would never be able to catch up (I think this was scaling workshop 2015).
No, bandwidth matters more than threads.
The "drastic" future of which you speak sounds like FUD to me.
However I would highly recommend using a Xeon anyway simply to get ECC - it's worth it. As transistors continue to get smaller, the bits flipped by cosmic rays increase.