I’ve had 6 LiFX BR30 lights on the front of my house since 2019. At first, they were pretty decent. One would fall off the network every other month, or so, but that wasn’t much of a pain. Lately, multiple lights will drop off the Wi-Fi every week. I’m at the point where I will either replace them, or install smart switches to just turn them off/on like normal lights. Looking around, I don’t see much in this size that are rated for outdoor use and support multiple colors. The current ones are set to Ukraine colors since the invasion, and I also change them for holidays. Ideally, I’d like to find something supporting zigbee, thread, or z-wave - pretty much in that order.
Mines are not outdoor rated, they are just bulb behind (don’t know the word in English) https://duckduckgo.com/?q=applique+extérieure+lumière+&t=fpas&iax=images&ia=images
Here is one outside rated (but should have more available) https://www.bestbuy.com/site/philips-hue-white-welcome-outdoor-floodlight-black/6326654.p?skuId=6326654&intl=nosplash
It is normal behaviour to have them locked to 2.4ghz (just like any other wifi smart things). And it is better that way as 2.4ghz has a longer wifi range than 5ghz.