Steam is Beta-Testing a Feature That Allows Anybody To Be A Playtester

The new Steam Playtest feature is currently under beta testing, and will allow any Steam user to try their hand at playtesting a professionally made game.
You get to playtest, they get to playtest, everyone gets to be a playtester!

Play the game = test the game. Why is this statement wrong

Steam Playtest will let developers run beta tests without using keys

Move-to-Earn Fitness App SPEXY is Now Live in Closed Beta

Steam Playtest (Steamworks Documentation)

Steam releases Playtest feature, allowing developers to invite

Desperately Seeking Playtesters

Who's up for beta testing DFHack on Steam? : r/dwarffortress

How to invite a friend to THE FINALS playtest - Dot Esports

Steam Categories and Playtest Feature Are Live

Evermoon to Launch Pre-Beta Test in Mid December

What are some good sites for finding beta testers? - Quora

Steam Playtest (Steamworks Documentation)

Comunitatea Steam :: Thrive: Heavy Lies The Crown