That said I currently don't plan on buying it, simply because right now I'm not heavily relying on the phone. It is however the first phone released in the last ~5 years that I'd call interesting and unique.
Individuals might be willing to contact you via other channels, but group chats won't move to another platform unless you are dealing with people who actually care about their privacy.
I don't use WhatsApp (can't use it due to not having an approved smartphone, and not wishing to accept Facebook's terms of use), and I miss things. Not a lot, and nothing critical, but my partner and I do miss out on some social things.
So you decide for the former.
By not supporting WhatsApp, it forces the user to solve the problem that he/she makes a very bad decision with respect to his/her privacy.
Hence my question in response to gregknicholson's statement:
>> This is one of the problems the Librem 5 is designed to solve.
> How?
It makes it easier for those who _want_ to switch, but don't have the confidence/skill/energy to figure everything out on their own.
Similarly, Disroot made it easy to switch away from Google, by providing a complete (for my purposes) drop-in replacement; Ubuntu made it easy to switch from Windows.
The problem rather is that many FOSS advocates are not willing to pay a multiple of the money (i.e. they do not put their money where their mouth is). If FOSS advocates were a very financially lucrative clientel, companies would care a lot more for them.