I'm also interested in this new eufy Smart Scale P2 pro - I couldn't find information on it yet on their website or Amazon, but the price looks very reasonable (Wirthings smart scale that is for sale on the Apple website is $149.95).
With respect to the 2.4GHz, you make a good point. I've found that many third-party devices are 2.4GHz only, for example some HomeKit products have this same specification. The Wirthings smart scale I mention above uses both bluetooth and 2.4GHz Wi-Fi. It took me a while to get my other 2.4GHz devices to work with my own particular Wi-Fi network, so this is good to keep in mind although other smart scales will have the same consideration.