I have friends who are professional musicians. They tell me that they are regularly asked to perform for free because "they like what they do". I have friends who are authors. They might write something as an one-off thing for a close friend's wedding or fiftieth birthday, but they don't, as a rule, write for free - yet many people expect them to. Nor should a psychotherapist who has 5+ years of specialised training plus at least a few hundred hours of therapy which they had to pay for, be asked to work for free.

Everybody doesn't need a paid professional. If you have friends whom you can talk to, that's great and I am rather envious. But a therapist is not a friend, and most people who lack the professional training cannot deal with complex traumas, severe depressions, aftereffects of abuse, for week after week after month after year. And there is certainly no love in the bargain.
(I won't comment on the original blog post since I don't inhabit the same world as the writer.)