I absolutely feel your pain. However, there is also the side that all this complexity must be handled somehow. The other extreme is that you’d have to compile all the software and its dependencies from scratch, as well as read and understand the source code.

In the end, it boils down to the people who actually care (like you, who is probably one of them) to exercise caution—looking at the output of curl https://some.rando.url/install.sh before doing the | sudo bash -c and constantly insisting on the validity and absolute necessity of signature checks, transparency, and so on. Meanwhile, all the other folks get at least a foothold in self-sovereignty without being completely smashed by the details of compiler flags.