No, that misses nuance. You can be self custodial of keys but use infrastructure so that you have to trust others on privacy, for example. From merchant side it's more complex but decent tradeoffs have been developed there, too.

You can make the argument that self custodial bitcoin full stop (i.e. not LN specific) is not viable for genpop, that is a real argument with some basis but it definitely isn't an argument that it shouldn't exist as an option, of course.