Complaining that an engineering company is full of mostly white males (in an industry which is full of mostly white mails) is an example of nothing. Red Hat started programs to push LGBTQ+ people in 2014, women in leadership in 2017, neurodiversity acceptance in 2018, black leadership in 2018. You may think all of those things are late, but as driven company missions which they spend real money on (and real money on community involvement on), it's not insignificant.
A "good-old-boy's club" at a company where only 25% of engineering was even in the US is a little mindblowing. The vast majority of RH's engineers when I left were in Pune, Brno, Tel Aviv, and scattered across Europe (eastern and western), with a reasonable showing from Brazil.
Open source is, for better or worse, a place where a cult of personality matters. "This is a bad idea and we shouldn't do it" isn't personal. It's how the community interacts. It's an invitation to argue back and say "this is a good idea because XXX". This is basically how any upstream mailing list works also.
While Red Hat did have some cultural problems, they were primarily around resistance to establishing an engineering presence in China (and it's hard to fault them for that -- my team was truly geographically distributed, and adding someone in APAC would have meant we literally never could have met at the same time), and regional cultural attitudes.
I left last summer, along with a lot of other people, but your comment is apropos of nothing Red Hat was from 2013-2021.