This is most likely true for Joel too. For less popular streamers, it matters much less whether or not they share their political views or go off on the chat for being shitty. They may lose some followers, but whatever, they can always gain more, or they can just rock with the number they have. It doesn't affect the channel or their lives very much. You can see that with old Vinesauce videos too - both Joel and Vinny were way quicker to the draw when it came to keeping chat in line, and they had a much higher tendency to make dumb jokes like the attack helicopter thing. They had nothing to lose; streaming was just a hobby for them. (And also humor was different then, but I digress.)
That's not the case for people whose entire livelihood is based around their channel, though. When you get big enough, your audience members have a much wider range of views and opinions, and you have to try and sate as many of them as you can, because this time, it DOES affect your life when you start losing viewers en masse.
As an example - if you only have 1,000 followers and maybe 10 subs, you probably won't be losing much if you make an offensive joke. Maybe you'll get knocked down to 900, or maybe one or two subs will drop, but that's not a huge loss because you didn't have much to begin with. But if you have 100,000 followers and 10,000 subs, and you get knocked down to 9,000 subs, that's a pretty noticeable blow. That's at least $5000 down the drain, all because you made some off-hand joke that probably wasn't that funny anyway. Why risk your entire career over something so stupid?
If memory serves, Vinny now streams full-time and doesn't work a day job. I'm going to assume Joel's situation is the same, given the weird hours he streams at, and the fact that I haven't heard him mention his other job in many years. By my rough guesstimate, both Joel and Vinny probably make at least $100,000 from their subscribers, and likely more if people are paying more than the low tier $4.99 or gifting subs to others (and I have definitely seen that happen more than once, in pretty high quantities - one time it was so much that Joel got flustered and just kept saying "wow that's a lot of money"). All they have to do to keep earning that money is spout some dumb memes, play some terrible games for a few hours, and then wait for the cash to roll in.
So by "growing a backbone," you essentially mean that they should flip shit on their clientele, the people who make up their main source of income, and risk losing the brand they've spent years building up and the quality of life they now have. So the question becomes - do you put your whole job on the line to soapbox, or do you suck it up and just keep plowing through and making your money? I think the answer's pretty obvious. It's much easier for them to just ignore chat for a few hours than it is for them to take some kind of self-righteous stand and risk getting stuck back in their old, shitty jobs.
