Just came across
this post.
It reminded me on my own dreadful weeks of confusion a few years ago when moving from good old MinGW to this version and naming maze. So can really feel with that OP and I feel that this should not be something that people who are new to C++ development should have to dive into.
So I think its a great idea to provide a codeblocks-working-out of the box package with that compiler and I would offer my thanks to and respect to the devs-team for the great work they are doing.
However, just for curiosity, I would be interested to understand if there was a specific reason to bundle the 64bit version of CodeBlocks 20.03 with the "x86_64-posix-seh" version (vs. including as well "i686-posix-dwarf")?