In a sense, yes.

It might even be a good thing to remove dead code -- what isn't there can't possibly cause trouble.

But it complicates product management: instead of a single binary and a bunch of feature flags, you now have a bunch of binary versions; and the number of permutations can get quite large quite quickly.

The cheating code is probably necessary. There are dozens of higher emission modes that an engine may go into to prevent damage in certain situations. E.g. low ambient pressure, high coolant temperature, slow wastegate response...