I have 3 accounts and 1 is a steam account. I added all 3 accounts and pinned them to be remembered. Next time I start the launcher, the launcher is asking me to add accounts still. If I click cancel, all 3 accounts are still there.
If I unpin only the steam account and restart the launcher, the launcher no longer asks me to add accounts and all is there but it always puts the steam account at the bottom and you cannot pin it unless you want the launcher to ask you to add accounts every time you log in.
Not being able to pin the steam account also will not keep the option to have all accounts, including the steam account, to start at the same time at the click of the Play button.
TL;DR
Fix the launcher please and make sure you check it with a steam account.