That is for what NDA exists.
When games have the notice "This game can cause headaches etc" , don't you play it?
Human nature… I receive a notice asking to not go in a party tonight… well I weren’t going before but after the notice let’s go to that party
But hey this was probably all planned by Valve.
There is no plan, this is how Valve has always operated.
Ever since the days of 1.6 and TF2, they've invited players to tests, they've invited community modders who they work with on certain updates to have deeper access to their backend(that blew in their face once) as well as inviting them to Valve's office, etc... They've never(or almost) made people sign NDAs for any of those things.
It's just trust system they have, probably coming down to their libertarian principles.
The Verge's journalist being wilfully confused about the why's and how he was banned when he is completely aware is eyerolling. As for the game dev article... It is also going full leap of logic and trying to put hypothetical scenarios that the evil Valve might just ban everyone's account because they can through market dominance(every publisher/platform holder can do the same) when they have never operated this way.
Lastly, it's kind of weird that some people online are portraying not signing an NDA, which can be financially ruinous if you do not follow the rules, as being worse than not signing one and just losing access to a playtest as a consequence.
A better to your party thing compared to The Verge's article would be something like this:
1. There is a swinger club in a moderately big city.
2. The club has a yearly cap on couples inviting other couples, the thing is known, but not that widely known.
3. A local lifestyle journalist got invited with their partner by another couple, they're completely aware of the club's rules.
4. That same journalist writes a steamy article about it, because it's relevant to the people of the city and their content.
5. They go to the residence where the freaky orgies are at but get denied and told they are banned.
6. They mad.
7. No NDAs were signed, she was just trusted by all parties involved and broke that trust.
In both cases, it is completely understandable that they have no longer access to the thing they had access to.
Nobody should be shedding any tears for them.