From the website about itself:
For a modern smartphone to be sustainable, at the very minimum it has to get security updates and it needs to be possible to change the inevitably failing battery. This site is designed to help with finding those phones (and tablets now too!): Phones that are supported by an alternative Android distribution are listed together with guides for changing the battery.
No, it is not. I found it while researching the current state the world of smart devices and which ones deserve a closer look or I should buy, if any.
The dropdowns are working for me, accessed via Firefox.
Battery swappable probably means it is intended by the manufacturing company to do so, not the actual possibility.