This is definitely not true.
> Even the norms around dating, picking people up in bars, etc. are changing because of these apps
This is true.
> so it's harder to find people in the real world.
This is sort of true.
By not using a dating app, a single person is relegating themselves to how things were pre-app. Some of those pre-app options are less common now, other new ways are more common.
The apps widened the dating door for certain people, specifically for people who are not particularly keen on getting out and meeting people (probably quite a few folks like that on HN) as well as people who are looking to get married asap[1]. That said, for people who get out and do things, meeting people to date is not difficult at all. Getting banned from Tinder for those folks is, at worst, a loss of a time filler activity (swiping).
I will also add that, of the apps, tinder might be one of the worst in terms of quality match ups.
[1] Apps are also good for highly desirable dates since their pool goes from big to biggest, but those folks aren’t really the topic here since they aren’t short on access to dates with or without an app.