The problem with Tulsa is multi-faceted.. but the single biggest issue would be hotel space..
Tulsa actually knows this is what keeps really large events out of the city and there are discussions ongoing about how to deal with this..
Despite all the new construction of hotels in downtown Tulsa, the city is still behind while Oklahoma City and others are investing in hotels with enough capacity to meet the
tulsaworld.com
specific to the tulsa expo center area, there are very limited upper end full service (4 star) hotels in the immediate area which is what an event like DSC or SCI typically requires.. so most attendees and exhibitors would be commuting rather than walking or taking a short uber daily.. which would be a very big issue..
Personally I like Tulsa.. the event space is big enough.. its a reasonably short drive for most of the regular TX attendees, etc... and Im not one to care about staying in a hotel close to the event (wife is an executive with a hotel management group, so we get great hotel discounts and generally stay wherever we can get the best rate.. ).. but I don't think it would be appealing to most of the other people that go to DSC..