Good point. It would be a perfect storm if all three kicked on at the same time, but very unlikely. To feel more confident I should probably look at the surge rating for those freezers. They're both pretty new, which makes a big difference. My parents have a 30 year old freezer that I swear dims the lights in their house when the compressor kicks in.
Correct, most newer devices (fridge, saws, dehumidifiers... etc) have capacitors and other electronics on them to reduce the inrush at startup of motors. Without going into a long boring explination... Electronics such as TVs and computers are very sensitive to surges and inrushes on the power grid, and consumer electronics has evolved to support demand. So, indeed, if you have a 30 or 40 year old refrigerator, it may not be as kind to the power grid as a modern one. However, even most newer GFCI's have evolved to better cope with this. (The fridge tripping the GFCI was a real thing back when they first became "standard", but this is largely a thing of the past now)