Here in the US, the NEC specifies a one-foot separation for low voltage unless crossing at a perpendicular angle. Low voltage is generally a specialty, so a lot of electricians don’t know.
The bigger issue is that there are tons of electricians that never went through apprenticeships and who never picked up and read a copy of the code (which has major changes every three years). The result is a lot of cargo cult installation which may or may not actually be correct.
The bigger issue is that there are tons of electricians that never went through apprenticeships and who never picked up and read a copy of the code (which has major changes every three years). The result is a lot of cargo cult installation which may or may not actually be correct.