Leaving gas in any motor for more than 6 months even with stabiliser is
not the best thing gas still deteriorates but slower. Most manufacturers
recommend only 3 months gas storage, you do risk gumming the carb. Sure
Either-Starting fluid works, but needing it indicates a gummed carb or
junk gas, why risk it for a 100-150$ carb rebuild.

A gen needs only to be run every 6 months to keep the gen head from
possibly loosing residual magnatism, any load induced while running will
remagnatise-charge the field.

Running for just 5 minutes doesn't fully heat up the oil to burn out
blowby pollutants in the oil. I keep my gen empty of gas and pour in
only enough for a 30 minute test, and run it dry. A test must include a
load even 100 just watts, to be sure the gen head stays magnetized.