One thing that has bothered me when listening to classical music with the sheet music also scrolling by is its persistent use of 5 or more ledger lines for low enough bass clef parts instead of ottava bassa lines.
Examples (all pulled from public domain scores on IMSLP):
Camille Saint-Saëns's Prélude et fugue, F minor, Op. 52, No. 3 - published by Paris: Durand, n.d. Plate D. & F. 2339. Reissue (new engraving) - ca.1900
Sergei Rachmaninoff's Prelude in C Sharp Minor, Op. 3, No. 2
Frédéric Chopin's Prelude in C Minor, Op. 28, No. 20
I find this use of 5 or more ledger lines below the bass clef to both be less readable than ottava bassa lines and against the tendency for notes above the treble clef to use ottava alta lines instead of 5 or more ledger lines. (At least, I've found notes above the treble clef to much more commonly be found with ottava alta lines instead of 5 or more ledger lines.)
Examples of ottava alta lines for notes above the treble clef instead of 5 or more ledger lines...or even fewer ledger lines than 5 (again, all pulled from public domain scores on IMSLP):
Camille Saint-Saëns's Prélude et fugue, F minor, Op. 52, No. 3 - from the exact same score as the other excerpt from that piece:
Franz Liszt's Tarantelle di bravura d’après la tarantelle de La muette de Portici, S.386
Franz Liszt's Grand galop chromatique, S.219
Why does this double standard regarding the use of ottava lines vs. ledger lines exist? Why are notes with 5 or more ledger lines so much more common below the bass clef than above the treble clef? Why don't publishers pick exactly one, more readable standard and stick to it?