It would of helped if you stated what the firmware update procedure was in the first place. What is used and where did you get the file from.
I don't know about Mac, but I (and most TV manufactures) would like to assume, using a USB flash drive, it would be formatted to FAT32. Then would further assume it would be through a Windoz PC. You are lucky you didn't "brick" the TV (though I never heard of that happening before).
Abundant OTA television is what makes this country different from all others. Lets keep it this way. If you like Wi-Fi so much, OTA fits right in. After all, it is wireless.