Maybe the flag no-exe should default to False rather than True.
Trying to install the executables with v2-cabal is a bit awkward.

$ cabal install yaml
Resolving dependencies...
cabal: Cannot build the executables in the package yaml because none of the
components are available to build: the executable 'yaml2json', the executable
'json2yaml' and the executable 'examples' are all marked as 'buildable: False'

I discovered the flag no-exe which defaults to True (!?), so it took me a while to discover how to unset it.

$ cabal install yaml -fexe
<<ditto>>

$ cabal install yaml -fno-no-exe
<<ditto>>

$ cabal install yaml -f -no-exe

The last finally worked, after rtfm.

Having a positive flag exe that defaults to False so that -f exe does the job would be an alternative to turning no-exe off by default. But really, if you type cabal install Foo, you want to install Foo's executables.