That really sounds awful, though - unfortunately - not really new.
Still, right now - with not much of actual experience with FP3s out there - I would expect the FP3 to fare way better.
Here (in a techcrunch article) Bas van Abel explains the core reason for my optimism:
Fairphone 2 goes beyond the idea of repairability. It’s more a show off phone in that sense. And that also comes with risks
I myself have disassembled my FP2 for demonstrating the modularity way mooooore often, than for actual neccessity.
The connections of the modules are weak, the phone in itself is rather flexible and the easy to open click-cover is doing anything but sealing the electronics. Therefore just from carrying the phone in your pocket, it tends to collect dust and dirt and humidity.
The most giving part is the display. With the FP3 it is fixed by 13 (!) screws, while it is clipped on with the FP2. And, as far as I know, they started with less screws, adding one at a time; the last one only for the final first batch production. The latest testphones came with 12 screws only.
This is the reason, why I consider us FP2 users kind of “beta-testers” of modularity an the FP3 the result of all the good and bad experiences.
Just compare the teardown of both phones on iFixIT:
The difference in design is obvious and to me the new modules and the entire construction give a much stronger, more sturdy and rigid impression.
Obviously, this is just my guessing, as I am still waiting for my wifes FP3 to arrive.