As I wrote in another post earlier, Librem 5 is trying to kill too many flies with one stroke and this leads to many customer groups being semi-happy instead of one customer group being fully happy.
It is what Germans call the “eierlegende Wollmilchsau” - the Pig that lays eggs, gives milk, and gives wool.
There are around 4 different target groups that could have been 4 different products and for some of these different Products Purism could have opted for a SoC from Qualcomm or whatever instead of developing from scratch with an older generation CPU. That would have sacrified on some awesome bells and whistles but could have delivered better experience to some of the potential users.
Some people just want a working Linux smartphone Mint style as an alternative to Android and iOS. Not everybody wants to to be completely blob free. Some people just want it to work and to be a little bit more trustworthy than Android or iOS. Raspberry Pi is not blob free and is a total success. And maybe this could have been a better ground for attracting people to develop apps for mobile Linux.
Another approach would have been to go for an ever slower CPU and to not make Librem 5 a general purpose computer, but a reasonably secure mobile phone with reasonable battery life. If security is the main focus, then the user is not getting thousands of apps and features but just the bare minimum.