You can, but they have to be on separate accounts.
people just dont like paying for privacy, because non-privacy alternatives are all free basically
hell, how i had to convince my family to pay 6euros for threema… like it was a massive thing lol. but they wont mind spending 6euro instead for an expensive coffee or other crap lol
Yeah, but that’s the problem. You can choose either 1 user, or 6.
In western europe, Switzerland included, the average family/household is not comprised by 6 people, not even close.
While not arguing that if might be a decent price for 6 people, the amount of customers needing that is surely residual.
I for instance, could see myself paying for a family account and trying to have my mom and sister onboard. But I ain’t paying for 6 accounts, because I’d have no use for half of them.
That’s the reason why I went with Proton. 
It’s actually fascinating how my view on this privacy matter changed over the time.
When I started my Unlimited subscription I cared kinda about it, now I’m kind of “scared” of the big buck companies due to what they do, I hate that they make money off me and MY damn data.
As of now I’m trying to 100% transition from Google Facebook and Microsoft to Proton. Only thing missing that stops me from transitioning from Google is the photo memory feature thingy. Facebook switch is made hard do to no proton chat (I know, telegram, threema and signal are a thing but almost none of my people use these).
Last but not least, Microsoft. Can’t really switch to Linux due to that everything is optimized for windows, especially games which are like 30% of my free time, otherwise I would’ve switched ages ago especially because of the little control you actually have on windows.
Wow this was a totally unnecessary comment almost non related to yours, but I needed to get that off my chest.
If you read it, thanks a lot and have a nice day, stranger 
NP. I find most hardest is Google for lots log ins. As for Microsoft, my work use Office 365 and all that suit. Hard to get away from them.
I understand where you’re coming from.
For me, I was able to delete my FB account in 2013, and never went back. I am still able to keep up with my close friend circle over email, chat, phone, text etc.
Microsoft: Migrating a couple of outlook.com to proton didn’t take much effort. Also switched to Linux & macOS for all office/personal work, for gaming I chose PlayStation & Nintendo. If I want, I might get a Steam Deck, but I haven’t found any game that I am missing in console.
Google: I migrated all but one Gmail address. That Gmail is used where proton/alias is not accepted and YouTube history. Photos go to iCloud, NAS daily, weekly backup to backblaze.
The only big tech I chose is Apple, a lesser evil than Google & Microsoft in my eyes.
I use 365 for work too (could use different services too) but to be honest I don’t really care. It’s not my data really but my companys so mehh, you know? If you’re also using like teams and stuff it’s a different story. Lucky for me my company uses self hosted services for chats and stuff