It doesn't take a direct lightning strike to fry delicate electronics like a computer or phones. And surge protectors do not provide any protection against lightning whatsoever.
The lightning strike could have been miles away, it would not have to be right at your building. There could even have been a ground strike in your neighborhood that has no physical evidence you could see. And it wouldn't even have to be a ground strike - cloud-to-cloud strikes can generate as much EMP or EMI as a ground strike.
The EMP/EMI induced by lighning could also have come in via your phone line or internet connection, not just the power line. Even the ground line can end up being a conductor.