Google shows similar amount of results. What is the difference in grammar and usage senses?

I don't know but in fact I came across "背が高い" yesterday in a story I'm reading.

I've seen "背が高い" in other places too but never "背の高い".

が can be replaced by の in modifying clauses:

彼は背の高い。 wrong, should be 背が高い.
彼は背の高い男である。 - he is a tall man (背の高い is modifying/describing 男)
背の高い男性は背の低い女性を好む。 - Men who are tall prefer women who are short.

or with a different phrase...
お前がやった。 - you did [it]
お前のやったことは間違っちゃいない。 - what you did isn't wrong. (お前のやった is modifying こと)

The 'no' replacing 'ga' in modifying clauses is pretty usual, not just limited to se no takai.

I HATE when they use "no" instead of "ga" in a modifying clause!

But seriously, do native Japanese people prefer one over the other, or is it a matter of personal "style"?

As I've noticed, people tend to us の over が in subordinate clauses to avoid the repetition of the same particle.
So something like 背が高い人が言った would become 背の高い人が言った

RandomQuotes Wrote:As I've noticed, people tend to us の over が in subordinate clauses to avoid the repetition of the same particle.
So something like 背が高い人が言った would become 背の高い人が言った

Yes...like what they call in English "elegant variation".

I actually find it easier when の is the marker in adjectival clauses.