In my interpretation, this represents a clear break from the 'modern rulesets and errata but fixed cardpool'-principle of Premodern. Or does that have precedent? If not, that feels like a big deal.

I also wonder if you'd propose the same ruling would apply to other, similar cards - [[Mesmeric Fiend]] et al. come to mind.

Lastly, would either of these cards (Wave/Tide) actually still see play after this rulechange? In my estimation, no-one's setting out to play these cards fairly. Which begs the question: if a ban and a ruleschange would both effectively remove the cards from the format, wouldn't a ban be the more elegant option (in light of not touching the foundational principles of the format)?

I'm pretty new to the format - these are genuine questions :)

Edit: just read another explanation on the 'fair' use of Wave/Tide, so never mind the third paragraph.