It's a misconception that electrons are slower than photons. In a vacuum? Maybe. But you need a medium to use photons and in fiber photons go at 0.5-0.75c.

Electronic signals in copper propagate at somewhere from 0.66-0.8c.

The big benefit of photons is that they don't experience electrical interference, so you can often get a lot more bandwidth out of a arbitrarily sized photonic medium than an electronic one.

The actual latency of photons vs electrons is generally not relevant.