Well, if they did adjust the math profile on the likes of 300 shields, Montezuma and Raging Rhino, wouldn't it be nice if they told their players? It does change the game and some players may not want to play high variance games and are more than happy to play the likes of Steamtower that is so much less volatile.
I like the little box with info 4theplayer include in their slots.
Should be mandatory for all developers imo.
And like you say, if anything changes, a popup should tell you what has changed, and why.
They should make an industry-standard volatility-meter, and it should be mandatory for casinos to show that+rtp% on their website.