I have identified the source of the problem for Astroberry 2.0.1 not booting on Raspberry Pi 4B 8GB. The primary problem is caused by zram swap (enabled by default) which throws kernel internal error 'oops 207'. The source of this problem is not known yet. As for now zram is disabled by default. If you know what you are doing, you can re-enable it by running
sudo systemctl enable zramswap.service
Existing users
If you already use Astroberry 2.0.1 on other Raspberry version, disable zram swap before swaping microSD card to Raspberry Pi 4B 8GB. Run the following command to disable zram swap
sudo systemctl disable zramswap.service
and reboot. Optionally, run
sudo apt update && sudo apt upgrade
to get it fixed for you.
New users
If you just got Raspberry 4B 8GB and downloaded Astroberry 2.0.1, you will have to download Astroberry 2.0.2 version. Optionally, if you have other version of Raspberry, you can use Astroberry 2.0.1 image and fix the problem just like existing users.