I see spaces where there should not be, and I see missing brackets and $ signs.
To assign a value to a variable in shell script from an output of a command, you need to do
variable=$(command)
These are the main reasons I see those backticks all over the place:
The articles showing them are at least 10 years old.
Whoever wrote that article is very old and is shell scripting for at least 20 years, but never changed or improved or adjusted their skills in the past 10 years.
People who “do not care” about deprecated stuff, because “it still works”.