Jerry said this, and it does seem like a subtle dig to end the Dez rumors, but Lamb already said he's wearing 10.
This generation of WRs seem to prefer the 10-19 range in the NFL (single digits in college).
I've had multiple grown, legally adult college WR's cry when we assigned them 80 series numbers. Like try to go over my head and go to the head coach to get their number changed, try to tell the equipment manager it's a mistake, and even bully other kids for their numbers.
Same deal if we give a safety or CB a 40 series number. I've told safeties "Do you not know who Ronnie Lott is?" and they said "No".