If you're talking about 'counselling' then yes, a friend can do it about as well as a trained counsellor. But remember that the evidence base for counselling is weak; that people often feel worse with counselling; and that counselling is sometimes actively harmful.
> covers something like 80% of 6 therapist visits, and after that it's all on me.
That's a shame. If they covered 100% of 8 visits they'd cover most people who need CBT.
> I've thought long and hard about how to solve this (maybe have a service that just handles all the idiotic HMO stuff for you to make it as low-effort as possible),
Maybe just "buddying" - someone visits or calls you and talks to you and watches you while you do all the stuff you need to do. This builds self-reliance.
But yes, anything medical is really tricky.
On the flip side, going to a therapist is just paying someone to pretend to be your friend for a while. My insurance (Kaiser; about $600 per month) covers something like 80% of 6 therapist visits, and after that it's all on me. This is probably the worst part of trying to seek help; the sickness basically prevents you from taking all the steps necessary to start getting better. I've thought long and hard about how to solve this (maybe have a service that just handles all the idiotic HMO stuff for you to make it as low-effort as possible), but I still don't have a good solution, and "hacking the medical industry" has traditionally been a non-starter.