I’ve had a similar issue. It seems that writing a working SD card image is very finicky or error-prone for some reason.
I wanted to remove my existing Manjaro install with a different flavour. After trying four different SD-cards (all four high-quality, bought in reputable stores), three different SD interfaces, and both “dd” and Balena Etcher, I was finally able to get an XFCE image of 20.08 to actually boot.
The working combination was an 16GB Sony card; with Balena Etcher on an Ubuntu installation; using the built-in SD reader on a Lenovo X260.
Notably, the same (verified) downloaded image, on the same Sony SD card, failed to boot properly when I used “dd” on my PBP. I get the exact same thing you do: A spinning boot logo, and nothing else.
Same image and Balena Etcher using a USB SD interface writes fine and verifies with no issue, but the PBP doesn’t even recognize it as a bootable image. An earlier (20.04) image on a different SD card written using that USB SD interface boots just fine.
All these cards are perfectly fine when opened as a file system, and verify fine. Perhaps something is broken with the bootloader. Notably, rebooting doesn’t work either with recent images; the screen becomes garbled.