I think that's not a bad thing. For big companies like that it is impossible to drive them out of the market with a competing company, so if you want to change it makes sense to do so from within. Especially since its such a powerful corporation they will always find people to replace the ones that leave, so your leaving doesn't actually help your cause all that much. Much better to stay inside and exert your power from within.
> So instead of moving on, lots of frustrated employees burn out trying to change the company from within.
(Quote from the post above yours, emphasis mine.)
I read the post you're replying to as saying they didn't understand why people don't just go work somewhere else, rather than burn out with futile attempts at trying to change the corporation from within. Whether they are right or not I can't really speculate in, just thought it interesting that we seem to have had different takeaways from the comment.