There's a website called NameMC in this website you can ask for the data of any* Minecraft account. UUID, capes, creation date, etc.
So, how does it work? I'm asking this because of two pages in particular, new skins & names apparently (according to the FAQ) NameMC can get the skins of all of the Minecraft accounts in sixty second intervals and change them accordingly, What? Wouldn't there be a Rate Limit or at least a safe guard in place to stop one IP from pinging Minecraft's servers Millions of times a minute? Also how can they get all of the Minecraft names, wouldn't that also require millions of requests? To my limited knowledge of the Minecraft API I don't think there's a list of all of the Minecraft accounts and their skins so how does it work?
How does NameMC get all of the registered Minecraft names?
How does NameMC get all of the skins of the registered Minecraft names?
There are a few other live sites that fetch and display username history such as minecraftuuid.com as well, might be worth checking them out and contacting them as Tim doesn't seem to respond much on Twitter.
Can you search Stacks645747? I want to see if I can find it (first it was on java but when I got banned I deleted it, now the one that exists is the bedrock one) but it keeps telling me to update my browser and I don't want to
EDIT: I also want to see if you can find my skin when searching my username
I'm currently in an aggressive e-mail chain with them over my rights to what they are showing. Mainly because I didn't publish anything they are using on their site, they just stole it and called it a day while letting people steal my skin when I never published it for use anywhere except for www.minecraftskins.com and I am on good terms with them. They keep using Mojangs eula against me but I don't have a mojang account as I use my microsoft. So I definitely don't approve of them and I need legal help to keep pushing against them.