I think the deeper question is: Are you truly being allowed to opt out if you can't disable (or aren't ever prompted to disable without knowing an arcane set of menus) the UI elements (e.g. the aforementioned prompts on password fields, or the prompt to install an app whenever opening the mobile web version of a site) that serve as an advertisement for the specific service?

To be sure, this isn't just restricted to "please install this" dark patterns, and in certain ways it's been central to the ad-supported business model ever since the first television ad was shown on a network channel. But arguably we shouldn't give any of these examples credit for truthfully being "opt out."

I guess if you define "forced" as "completely 100% impossible to avoid or prevent" then yes. But I think it's reasonable to say that "forced" is acceptable shorthand for "coerced by dark patterns in such a way that 99% of actual users will end up doing what the vendor wants whether they want to or not".

For a few things (the one thing I'm familiar with is the lock screen if you've left the "show random pretty pictures" option turned on, but I think there are a few more places besides that) Microsoft does force links to open in Edge instead of the default browser.