I don't see myself buying D&D 2024, because I haven't seen much of anything that has impressed me with the playtest (just as I have not seen anything from WOTC after the core books that made me want to continue buying WOTC products for D&D 2014). On the other hand, there have been several 5e third party products for free as well as for pay on DrivethruRpg and DMsGuild worth picking up (imo).
Provided, players can still get the 5e (2014) PHB for a reasonable price, 5e will remain one of several choices along with Savage Worlds, Icons: Assembled, Mutants & Masterminds, Magnum Fury, Black Star, Barbarians of Lemuria, Honor + Intrigue, Tinyd6 games, Everyday Heroes, Spycraft, D&D 3e, and a few other rpgs.