Last week we had a terrific lightning storm, and it hit the TV mast, rotor, and antenna. That was witnessed by a neighbor. Although I had turned off a lot of computer equipment and unplugged quite a bit of it, I was on a trip but my wife was here, it knocked out the internet card on this computer and a hub in another building. Interestingly, the hub was not hooked to the electrical outlet. I had pulled it out. The rotor controller got zapped too. All else was fine. Maybe I just haven't used some other device that was damaged.
Terrain-wise we are really exposed, but do not have frequent lightning storms. There are no big trees near the house, and none higher than the house. Well, one. A ponderosa 50 feet from the house. We are at the highest point in the sparsely populated neighborhood. The closest home to us is200'. The older neighbors around here said the storm last week was easily the strongest and most dynamic they've seen in there some 30 years here. No one thought to take pictures!
I'm quite sure the rotor, antenna, and mast are not grounded. The question becomes how to deal with a future strike. One is to ground the mast and rotor. Another is to just put up a lightning rod on the roof. Another is to just take down the antenna completely. We really don't use it any more. I've left it in place with some thought I might want to use it for local stations, which really are 60 miles away. Otherwise, we are on DirecTV.