Well the new motherboards with AMD Ryzen 7000 cpu's are DDR5.
And like DDR3 to 4, they aren't interchangeable.
If you're keeping with that spec ^^, it depends on what you want.
If you're already stretching your budget, 2 x 16 2666. If you can afford it, 3200 is the sweet spot for DDR4, bang for buck.
DDR5 knocks DDR4 out of the park.
I'd better mention, I'm only regurgitating what I've been reading in these forums recently. I'm an old computer geek, catching up slowly on new computer gear. Not anything like as expert as a lot of other members in here. They know what I'm just starting to learn.
DDR5 doesn't knock DDR4 out of the park unfortunately. Did you read that somewhere on here?
There is a marginal gain in game, which extends depending on application, but we're going to need to wait for the faster RAM offerings from DDR5, with tighter timings if possible, before we see it really stretch its legs.