You can never be 100% sure, but there are protective factors that make it less likely, and they mostly boil down to incentive structure:

• Ownership - Is the project run by a non-profit? A for-profit company? A hobbyist? This is the best indicator of a project’s long-term trajectory, because it generally indicates the purpose behind creating it.
• Business model - How does the project make money? Donations? Subscription? One time payment? Generally models where you can outright purchase a copy of a particular version is insulated against future updates you don’t like. Donations protect against exploitation, but run the risk of the project being unsustainable and abandoned.
• Source - Open source code isn’t a silver bullet, but (especially with good licensing) it can make enshittification less likely as it’s a lot easier for dissenters to spin up a fork / competitor. It also makes it very difficult to hide sketchy stuff like data collection and back doors.
• Red flags - You should avoid anything that is SaaS, backed by an investment firm, or publicly traded. All of these involve incentive structures that encourage and reward exploitation of consumers and employees for increasing profit margins.

You dont.

Obviously copyleft license and stuff that embraces FOSS is great, but open source licensing doesn’t bar the key developers paywalling features. You just have to avoid building digital systems around a single point of failure where possible.

Enshittification is built-in to Capitalism, the Tendency for the Rate of Profit to Fall forces it. FOSS and whatnot is safe.

Just use open source software?

Personally, I’m at the point where I try to only use community-developed software. I’ve seen it too often that even projects which are nominally open-source start becoming cunts…

I don’t think you can. But if it’s open source and popular, there might be a chance it will have a maintained fork should that happen.

Freemium feature creep might be a sign things are changing for the worst, as in, if more and more features are being added to the premium plan and the free version is stagnating; to the point the target public of the premium version is creeping to average users instead of aiming at commercial or power users.

I think it is not possible to avoid it in all cases, but the reputation and business practices of the controlling company are your best indicator. Any changes to a company’s culture may give signs if a piece of software may start to employ anti-consumer tactics.

Naturally, being closed source and in a dominant market position (i.e. a monopoly or near-monopoly) would make it easy for a company to start pulling these kinds of tactics. Sometimes even formerly reputable companies with open source software can try to do things like this after buyouts, changes in management, pressure from capital investors to increase profits, etc.

Generally, open source programs will be harder to monetize than closed source programs, as someone can fork the code and take out the disliked features. See Ungoogled chromium vs Google Chrome, VSCodium vs VSCode, Rocky Linux vs RHEL, etc.

I’ve been focused, lately, on separation of concerns. Yeah, using FOSS tools is great, but I’m also asking myself how much losing a given tool will impact me if I start to rely on it.

This past weekend I finally broke away from ProtonMail. After what the CEO has been saying, and because of other annoyances like being unable to use anything but their clients, it was finally time to rip that bandaid off.

Unfortunately, I made the mistake of using a standard protonmail.com email address, so now I have to tell everyone to stop using that. Also, I was a heavy user of SimpleLogin for creating email aliases for basically every service I signed up for, and now I have to switch all of those.

I should have learned this lesson when I left Google, but this time I will be using my own domain. I also took this opportunity to leave Cloudflare entirely.

Now I have a domain for my email address and my website through porkbun, but can transfer that to another registrar if they start to suck.

I use desec.io for my DNS needs instead of the built-in porkbun DNS tools to make it easier to switch to a different registrar if I need to. They’re a non-profit, and it’s open source software that I could potentially selfhost in the future. This also replaced Cloudflare.

I use fastmail.com for the actual email service, which let’s me use the apps I like on my phone and PC to interact with email the way I want.

Fastmail also has a service like SimpleLogin, but instead I went with addy.io (also FOSS; also potentially selfhostable) with another custom domain at porkbun.

My website is a blog hosted by write.as, which is, again, built around FOSS and selfhostable software.

All of these pieces can be swapped out without affecting the others if need be, bringing switching costs to near-zero, and making it very customizable in the process.