And of course OneDrive, but you already said you don't care.
Honestly, if you don't care about those, it is perfectly fine to just use Windows with a local account. But there definitely are benefits if you are looking for a more Apple-like "everything is connected" vibe.
This is all accurate. However, there's one other thing, which is essentially SSO.
Basically if you sign in with a Microsoft account, you can sign into your PC with your Microsoft account username and password, which can be easier to reset from another device than going through the password recovery process for Windows.
Apart from that, your bitlocker keys are stored on your Microsoft account if you have that enabled on your main drive.
As an aside: if you have bitlocker enabled on your PC, be sure to back up the recovery key. Print it off, or save it to a USB drive and email it to yourself (the system won't let you save it on the encrypted drive for obvious reasons), or something. Bitlocker isn't bad, I just feel like Microsoft doesn't do a very good job at making people aware of the pitfalls of it when things go sideways. Basically, if you need to pull the drive for any reason as part of a recovery operation, then you'll need the recovery key to decrypt the data and gain access to it for the purpose of recovery.
Fair warning: anyone who purchased a prebuilt PC in the past 3-5 years should check on it (longer realistically), and make sure they have that recovery key. Most prebuilt PC companies (like HP/Lenovo/Dell) generally have bitlocker on by default and Windows does a wretched job of telling you any of this.
Bitlocker isn't bad, it's full drive encryption. That's a good thing for the most part and you should use it, especially with mobile systems, but please make sure you have that recovery key. I work in IT support and it's starting to happen that drives fail, and the client doesn't have the recovery key, so I can't even try to recover the data for them. It used to be trivial, just load the drive into a working system and grab what you need, but with bitlocker, even if you get a corrupted file that's required for Windows to start, but the disk is otherwise fine, your data goes away and will not come back without that key.