Why is the Home Internet Gateway functionality crippled?

This has been discussed a lot (and I mean a lot!) on this forum and on Reddit, and the short answer is that T-Mobile has decided (unfortunately, imo) on crippling end-user customization of the gateway settings.  

They are aware that many people don't like this and would like a lot more control, but that's just not the business model they want to follow. My old DSL service allowed me lots of control, and as a networking guy in my day job, I took full advantage of it.  But for me, I traded off that control for cheaper, faster internet.

At the rate that T-Mo is adding new home internet customers, I don't think they see the need to change their business model. This has the unfortunate effect of leaving many users without the functionality they would like/need. T-Mo seems OK with the "we're not the solution for everybody" approach.

In addition, even with the reduced functionality of the gateways, their tech support staff seem to be having a hard time helping people solve the problems they encounter. If they allowed a much more heterogenous gateway setup environment, I think tech support would have an even harder time helping people. Just my opinion.