I like this synergy with Matrix.

“The idea of a Matrix-native smartphone is unbelievably exciting. Matrix has always aimed to be a decentralised encrypted alternative to the public telephone network, and the Librem 5 makes this all the more true. With truly open communications and a truly open operating system, this is a vision of a world where users are back in control of their communication and their technology, rather than being trapped in proprietary communication silos – a world that cannot come soon enough!
— Matthew Hodgson, Co-founder of Matrix.org

it actually makes me suspicious... I'm hopeful because such a phone is badly needed. I'm constantly worried that we live in a society where no such phone like this has existed yet despite the fact that it totally should and there is really high demand. It's a constant reminder of the powers in control of our society.  Their webpage makes KDE sound like a second-class citizen. I have to wonder what else is just buzz and fluff and playing on people's wishful thinking.

Their webpage makes KDE sound like a second-class citizen

What do you mean?

From #^https://itsfoss.com/librem-linux-phone/ :

But if a big organization like Canonical couldn’t succeed with Ubuntu Phones, can Purism succeed with Librem? That’s the big question that can only be answered in future.

If I have to speculate, I think Canonical’s inexperience with hardware might be one of the reasons behind Ubuntu Phone’s failure. At the same time, Purism has a track record of producing top-notch hardware for Linux. Perhaps they will be able to do the same with mobile as well.

from their FAQ (way at the bottom, no anchors)

We will be working with both GNOME/GTK and KDE/Plasma communities, and have partnered with the foundations behind them for the middleware layer. PureOS currently is GNOME-based and our great experience with working with GNOME as an upstream as well as GNOME’s OS and design-centric development model; however we will also test, support, and develop with KDE and the KDE community, and of course we will support Qt for application development. We will continue to test GNOME and Plasma, and should have a final direction within a month after funding success. Whatever is chosen, Purism will be working with both communities in an upstream-first fashion.

It's a touchy issue, I understand. #^https://puri.sm/posts/librem5-gnome-and-kde-collaboration/ and I'm hopeful... but still, I will believe it when I see it kind of a thing.

I'm suspicious because I'm suspicious of everything silicon valley, but the matrix project in particular seems pretty hipster and out of touch to me, that's why I say it's actually a negative for me that they are involved.

I didn't have the impression they were a "silicon valley" thing. Is there anything specifically that irks you about them or is it just a general impression?

From #^https://matrix.org/docs/guides/faq.html#who-is-funding-matrixorg :

Who is funding Matrix.org?

Matrix.org is currently (Sept 2017) funded by the community, through a combination of community support (via Patreon, Liberapay, Bitcoin and Ethereum), corporate sponsorship, and grant funding. Current Elliptic-level supporters on Patreon and corporate sponsors can be found on our supporters page. If you would like to support the core Matrix team as a member of the community, please visit our Patreon or Liberapay pages, or you can send us Bitcoin at 1LxowEgsquZ3UPZ68wHf8v2MDZw82dVmAE or Ethereum at ETH 0xA5f9a4f9E024F6D727f7afdA9257e22329A97485. If you would like to sponsor the team as a corporation, or are interested in paying for prioritised or custom development, please get in touch.

For the first three years of Matrix’s development (2014-2017), most of the core contributors worked for Amdocs, who paid for them to work fulltime on Matrix. In July 2017, Amdocs considered the project to be sufficiently successful that it could now self-support and so stopped funding. The majority of the core team is now employed by New Vector, an independent company set up to hire the team and support Matrix’s development. Other contributors are funded by their own employers or donate their own time to the project.

I know Purism's (maybe previous) marketing person, I am pretty sure they are San Francisco and not Silicon Valley. But maybe it's about matrix which I know nothing about :)