Well said. More generally, it is often difficult to disentangle someone's motives & beliefs (and therefore the things they say) from their occupation. After all, the more deeply you believe in something, the more likely it is you will try to make it happen, the limit of which is making it your primary career.

Suppose someone working at a travel website writes a post about the problems with the existing travel industry. A large percentage of commenters will then pipe in with, "of course she'd say that, she works at a rival firm!"

But is that the causation? Suppose an "independent" person writes the same blog post. The reactions to the blogpost would have been different in that case, even if that person later goes on to start a travel firm.

In other words, is the causation:

1. start/work at travel firm -> try to encourage people to switch to them -> write blog post

2. dissatisfaction with travel firms -> write blog post -> decide to start competitor

(And of course there are many other possible causation chains.)

Yet most commenters seem to assume that (1) is not only the most likely option, but often the only possible explanation.