I’m inferring from the language of the post that OP is against this policy change, but I’m not sure I follow the argument. Why is it problematic that Plex is asking for money?

Good point. This journal was just delisted from Clarivate because of integrity violations as well.

This study is unscientific garbage and should be retracted.

Their “simulation” of making tea involved 300 teabags boiled in 600ml of water at 95 C while being stirred at 750rpm for an unspecified amount of time. They then took counts using undiluted samples of that liquid.

It isn’t clear why they chose such an absurd methodology, but it is absolutely spurious to draw conclusions from this about teabags used under normal conditions.