Why is `instance_variable_set` necessary in Ruby?

Question

What's the point of instance_variable_set? Aren't these two lines the same?

instance_variable_set(@name, value)
@name = value"

Answer 1

In the case of a "simple" variable assignment for an instance variable like:

@foo = "foo"

You couldn't do

"@#{foo}" = "bar" # syntax error, unexpected '=', expecting end-of-input

But you could do something similar with instance_variable_set:

instance_variable_set("@#{foo}", "bar")
p @foo # "bar"

As per your question Aren't these two lines the same?, for that example they're similar, but isn't the use people tend to give to instance_variable_set.