This is exactly it. If you want to improve at SS, even if these guys are available, here's what you have to pay:
Seager - 8 yrs, ~$32M/year
Lindor - 8 yrs, $34M/year
Witt - 11 yrs, $288M
Swanson - 6 yrs, $26M/year
Henderson - empty the farm
Bogaerts - 10 yrs, $25M/year
Bichette - empty the farm
Turner - 10 yrs, $27M/year
McLain - empty the farm
Correa - 5 yrs, ~$33M/year (if he's even any better at the plate)
It's either empty the farm or take on significant long-term financial risk (plus prospects), and few of these guys are even going to be available. Compared to what you have to give up or pay for those guys, Adames is worth much more than a comp pick.