Let's think about this together:
1. Horus would obviously counter a spell-heavy deck like Spellbook, but getting out Horus on your first turn is going to be difficult, and you *need* to get Horus out right away to survive. They probably use Treacherous Trap Hole too, so good luck defending Horus on top of getting him out...
2. Tower of Babel could dissuade the Spellbook player from playing the 4th spell card... and if you have 2 Tower of Babel, they basically can't play spells anymore. However, Tower of Babel itself is very situational card, unless you yourself intentionally put 3 counters on them.
3. Spellbook of Fate can only banish one card, so you can technically defend against it if you have multiple defensive cards, then maybe, just maybe, you'll outlast the Spellbook user and turn things around.