The thing with thunderbolt is the ease of use. Most of people do not care whether their port is 10gbps or 40gbps, they just want USB-C. Thunderbolt is quite good at this because it can provide more speed to power users whilst still being user friendly. Secondly, eGPU is quite a niche market, so you cannot expect much support there. And oculink eGPU is even a more niche market. Needless to say, I would prefer oculink egpu to thunderbolt one.
On the other hand, framework is an enthusiast brand, so I would understand and be happy if their laptops had even these not so common ports.
FYI: some people are developing oculink expansion bay for the FW16