One by drivetrains certainly have their advantages, but many new gravel bikes sacrifice 2x drivetrain compatibility for ultra short chainstays and only accept 1x. Notable examples are Marin Headlands and the Gestalt X10 and X11. Others models that also accept 2x have their whole lineup equipped with 1x. If you also want to use the bike as a road bike, good luck with that. It's either climb hills or go fast with current gravel 1x drivetrains, depending on the size of your chainring. For me the new GRX gravel drivetrain from Shimano has been a godsend: a no nonsense subcompact 46/30 crank and a deraileur usable with up to 11-34(36) casettes or a 1x option usable with up to 11-42(46) casettes. If it wasn't for the gravel/all road bike I would have probably never gotten a proper road bike with skinny tires because it's only usable on roads that one shares with other motorized vehicles.
My first gravel bike came with 42t crank and 11-42 cassette. It's perfect for everyday use. You spin out at like 45km/h (or even higher if you can do high cadence) while the 1-1 gear allows you to climb pretty steep hills.
Sure, it's not enough for a road race and I prefer 2x drivetrain these days as I do a lot of distance on pavement but I still think 1x is just a better option for most recreational cyclists.
