Thomas is right.
That said, I have cracked open half a dozen each XTs and ATs, and probably 2 dozen 122-key terminals. The majority of XTs and ATs had good or acceptable foam, perhaps 2/3 to 3/4 of them, but 80%+ of the big boys had poor-to-utterly-disintegrated foam. I theorize that while XTs and ATs were consumer products kept indoors, terminals were corporate/industrial machines that were probably tossed into warehouses, at best, when decommissioned.
Having replaced foam often enough that I am proficient at it, I consider it de rigueur for a rehab, and only bypass it occasionally.