Yeah, one of the better things they've ever had, but ultimately it's just edge joined 2x2s, so depending on where you live you're likely to get some cupping/warping over time.
They probably still have similar wood countertops you can buy and use for the same purpose, though.
Nope. At least in the US, all the countertops are particleboard, laminate or quartz. There's a butcher block themed particleboard but that's the closest you'll get now.
I'm still finishing up an IKEA kitchen, but the last I checked there were no solid wood options any longer. Used to be for SEKTION (and the Euro equivalent) they even carried solid ash doors and drawer fronts, those were discontinued a couple years ago. There are solid bamboo fronts (but no doors).
The closest you'll get now are particleboard tops with "thick" veneer. VRENA and MÖLLEKULLA use "thick" oak veneer; KARLBY, BARKABODA, and PINNARP use a "thick" walnut veneer. Veneer being IKEA's choice of words, not mine. These have traditional laminate on the underside.
SKOGSÅ uses "thick" veneer on all sides but is still a particleboard core.
They probably still have similar wood countertops you can buy and use for the same purpose, though.