I have been using Saifish as my daily driver and only phone since 2014. I bought a Nokia N9 secondhand in 2013, but the battery was not great anymore and I could not use Whatsapp on it. The choice for Sailfish was then easy. For 5 years I used the Jolla 1, which has received updates from 2013 to 2020. Since 2019 I am on a Sony XA2. I bought it secondhand and after a commercial license for Android app support it still felt very affordable to me. I you would want to start now, the Sony Xperia 10II might be the best choice with Oled screen and Aarch64 support.

Sailfish is being made by a small company with not that many developers, which means there are rough edges compared to Apple and Google. They can spend many millions on their software. I am very happy with Sailfish updates though and also very happy with using it.

The only Android apps I use are Firefox in its last v68 incarnation, and also Whatsapp. I'm lucky not to be tied in too much with all kinds of services :) For many services there are native apps.

And yes, it is not fully open source, which is a pity. The current investor sees no business opportunity in that, but to be real, without that investor, Jolla and Sailfish would not exist anymore. They are mostly a B2B company now, B2C has commercially failed around 2015. I do hear sometimes that more people are using Sailfish, but I haven't seen real statistics. There is also the Nemo project, which started with reimplementing the closed bits in Sailfish, and later deviated somewhat. If Sailfish gets more succesful, that is always still an option to force their hand, but I do feel the time is not right. I do have to say that the Linux community can be very critical towards its own community, sometimes getting to be toxic.

I would be open for a Pinephone, but it is mostly regarded as a developer phone right now. I will wait for Pinephone2 and hope things improve to make it more a daily driver. The Librem 5 is priced out of my league, though I do admire what they are doing.