But… Blaming people who are being fucked over by forces generally outside their control is not really going to help their or our situation.

The whole premise of the comment is that it's not outside of their control, they just chose not to be responsible for the agreements they make. If you have any better suggestions than blaming those responsible for the situation I'm willing to listen and maybe even change my mind.

Expecting or demanding “people” to just change is also not realistic. Even if they wanted to, time, effort, energy, knowledge, skills, and attention are all finite.

Is it more unrealistic than "we" deciding to change and find a better path forward than surrendering our digital lives to strangers? I'm able to self-host my own push server. I wasn't born with that knowledge. I had to invest time, effort and energy to gain the knowledge and skills. If I can, so can others. I am not an extraordinary smart person.

Still, long before one starts to self-host entire platforms like NTFY or Nextcloud Push, there's a ton of free to use services ran by idealists rather than capitalists. Or payed options with good terms. There's so much between just not caring and being ones own sysadmin that I don't think "don't have the time" is a valid excuse anymore. It's not just push messages, it's everything - as you point out:

This is just one important issue or source of exploitation among a sea of others.

Sure. And most people I offered a free Nextcloud account to said the same. And Mastodon/Friendica-accounts. And so on. It's like a technological mass depression, we can't do everything we need to so there's no point doing anything at all.

And today I'm running a custom ROM and no push services from Big Data while they're literally getting robbed of their phonebooks by Meta.