I got to (had to) re-install Windows 10 and Windows 11 again, so here's the skinny as of 2/5/2024. Rufus 4.4 offers some nice options for creating installation media from the official .iso's (which are free to download).

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Setting it up for local account and naming the user directory whatever you want is a big plus in my book. No need to enter an e-mail and password for Microsoft account.There's a few other things I like about the local account vs sign-in with Microsoft account. But, like I said, you can always add a Microsoft account later.
You STILL can activate it with a product key if you want to. As of today you also can still activate Win11 with a Win10 product key, or activate Win10 with a Win7 product key. You can probably get a Win10PRO product key for <$20, or find one for free.
The trick is when you do that, it activates and then assigns you a new product key. So you want to get it and write it down, find it by entering <wmic path softwareLicensingService get OA3xOriginalProductKey> in command prompt. This is important because Microsoft policy could change, and having the new key actually for Win11PRO might be helpful to you.
After uninstalling all the Microsoft apps I don't want (upgrading to PRO version allows you to uninstall more of them, but not Edge. Edge you just have to use it's settings to disable when it's not open) and then installing several apps I wanted, Win10 weighs in at 47.9G and Win11 at 64.8G installed.
I don't have a crystal ball, it could be due to my secure boot settings I'll be locked out of them both if Microsoft policy changes. I don't use either much anyway. I just like to keep my options open. For me I like having them installed even if I don't boot either for months. I think making a USB for each with those settings w/ RUFUS is worthwhile whether you have immediate use for it or not. And, for me, installing both with valid, activated PRO keys (while cheap or free to do so) and using local account log-in leaves me the most options possible.