He is generally right imho.
I have never had a desire nor seen a need for a union for me. But I recognize that there are many different types of careers in games. So I guess if game developers ever unionize then it would be multiple unions, not just one?
He frames the issue well. As anyone who is trying to recruit good games developers in 2019 will tell you, right now the power is with the talent, not the companies. In those circumstances I dont see how a union helps.
Its also worth noting that while the recent layoff headlines rightly make the news, any glut of talent is centered around certain disciplines but core fields remain extremely understaffed.
For example a senior engineer with games experience competent in C++, can walk into just about any games company they like.
I should note that a lot of the layoffs you have seen recently are also a reflection of the changing market eg: mobile is being hit hard with increasing UA costs and a customer hostile business model which, unsurprisingly, gamers from casual to core increasingly resent.
Its also the fact that games development is changing. You just dont need a lot of people to make a hit game anymore. This has a knock on effect for supporting disciplines, if you have a team of twenty then you dont need as many managers or production staff as you do with a team of 80, or 100.