I would be more worried about wind than lightening, but you do have a point.
The flag pole I use is a 20 or 25 (not sure which without measuring) sunsetter telescoping, all metal, but the mount is a "park on" mount, a flat aluminum sheet lying on the ground, with about 2-4 tons of Motor home parked on top.
There is a plastic sleeve, but to a direct lightening hit, it ... Won't matter.
Home was where I park it. but alas the.
2005 Damon Intruder 377 Alas declared a total loss
after a semi "nicked" it. Still have the radios
Kenwood TS-2000, ICOM ID-5100, ID-51A+2, ID-880 REF030C most times