Lots of AEC users actually would prefer subscription model. The hand-wavy economic main reason is subscriptions go from opex and purchases would go from capex and companies generally prefer opex to capex.

The business model of large AEC companies is a bit different than that of hollywood VFX subcontractors. The projects for one are already expensive and the data itself is a critical part of the deliverables (instead of just a rendering of the data).