Mazda has a new version of the Idemitsu high moly 0w-20 that's GF6. All oil manufacturers switched to GF6/SP years ago and many are already on the GF7 standard
because it's an old-ish engine design that was designed around the SM oil spec. Any SN, SN+, SP, spec oil that has come since will provide much better performance than SM
I have a hard time believing that any dealer would discount a 2025 CX5 by $7k, esp when the markup is only about $1k. Even if they held a couple grand on the trade that deal still doesn't make sense