Unless you are using the very best tubs that Veloflex or FMB offer then you can comfortably match them, for weight and rolling resistance with the best of the current clincher crop.
An alloy clincher rim will add a couple of hundred grams over a carbon tubular aero wheel, and unlike carbon alloy buckles. You can’t really buckle a carbon rim, you can bend the spokes it is laced with though or damage it with too much heat if you drag your brakes.
Carbon tubulars are great for race day, but a lot of the carbon race wheels with deep section hubs simply ain’t built for everyday use.