For the civies, all tier 1 means is funding. Tier 1 operators have near unlimited funding when it comes to training, equipment and resources. We when you hear tier...just think financial support.
Seals are great, they serve a purpose. The only reason they had that mission to kill OBL was because they were responsible for A-stan at the time while Delta was responsible for Iraq.
Delta went through the same scrutiny when their tier-1 program was started in 78. Every unit is specially equiped and suited for specific missions. If you noticed on the OBL mission, it was Rangers who were the quick reaction force. Rangers have always been QRF for tier 1 groups. Once MARSOC gains some tractions, I'm sure the Navy would rather thave them instead of Rangers as their QRF. Air Force PJ's work closer with Army SF while Air Force CCT work closer with conventional infantry. Funding and mission has a lot to do with it. No one size fits all.