It's a little ironic that a system like SBing which utilizes RNG is the most stable method of generating wealth via crafting.
To me it seems like they're trying to shift the balance of wealth away from the craft SBers, while providing greater reward for generating materia across all levels.
This patch only serves to (perhaps temporarily) drive up base costs for us, but benefits the ones SBing battle-type materia as they've now an outlet for the elemental III/IVs.
With the previous patch that saw a relatively high minimum NPC price for all materia added, direct result was 3-4x price hike compared to prepatch prices. Still workable, but forcibly designates a higher amount to the users generating all the crap materia we use in bulk. I don't think it stimulated activity like they'd perhaps hoped though? Which is why we now see this weird materia transmutation system, which only really seems useful for elemental IVs, perhaps IIIs. Everything else is mostly in the bracket where, as others mentioned, it would be more profitable to just MB them.
As for tier Is being high atm, I'm content to just sell them off in bulk at absurdly high prices, and wait for it to normalize a week or so down the line.