That's how I understand it. Routing nodes would be incentivized to support all available transport layers as it increases the odds they'll help route a payment between peers which don't have the same transports enabled.

Most LN nodes are Tor-only. So the demand for anonymity layers seems strong. Additionally, clearnet is difficult/expensive to setup (especially if you don't have a dedicated-IP because you're behind the ISP's NAT).

The pleb noderunners deserve a "middleground" transport with some anonymity, easy to setup, and more performant.