It has lots of small issues that add up to a frustrating experience for mainstream users.
And 90%(1) those are out of Linux’ actual resposibility because they are caused by third parties screwing up… sometimes even intentional (from companies producing lackluster drivers only having a fix cobbled together for Windows specifically -looking at Realtek networking for example- to ones actually going out of their way to block Linux (MS FUD included…).
(1) The other 10% exist on Windows or Mac also, but people just accept them because they are used to not having a chance to change it. Seriously the amount of obscure regedits or third party tools usually surpass the number of linux issues fixed by editing an easy to read txt file.
Decryption isn’t a problem if you use the systemd hooks when creating your initrams. They try to decrypt every given luks volume with the first key provided and only ask for additional keys if that fails.
I have 3 disks in a btrfs raid setup, 4 partitions (1 for the raid setup on each, plus a swap partition on the biggest disk), all encrypted with the same password.
No script needed, just add
rd.luks.name=<UUID1>=cryptroot1 rd.luks.name=<UUID2>=cryptroot2 rd.luks.name=<UUID3>=cryptroot3 rd.luks.name=<UUID4>=cryptswap
to your kernel parameters and unlock all 4 with one password at boot.