your idea is partially correct
how you get there…
a cap on salary is not going to produce the effect you want
your basic desire for less income inequality is shared by most of humanity
making things more equal sounds good
how you do it makes all the difference
socialist ideas are sometimes good
nobody wants a fire department organized on capitalist philosophies
or a library ( a capitalist library is a book store)
it's all about how you get the end result your desire.
tilting the playing field a bit, favoring the poor 'little guy' and taxing the bigger, more powerful slightly more is one way of getting to your stated goal of better income equality.