They could be talking about one of the mobile versions.
If not, and it is subscription-based, as an MMO player (and even MMOs are moving away from subs) I really don't see EAxis keeping up with the proper patch schedule. Weekly patches that sub payers demand? We can barely get one a month most of the time, never mind regular content drops. People who pay a subscription demand quality, demand content, and demand it yesterday. EAxis can't keep up with anything more sub based than EA Access. The mess that is the Sims 4 would have died 6 months into its lifespan if they had charged a subscription, and they know it...so Sims 5 better bloody wow. And it better be totally optional, or you lose 90% of your player base - who control a large portion of your demographic.
I, however, am making no judgments on whether or not I play the next iteration until I see it. I don't make decisions on rumor and conjecture.