All.the.freaking.time.
I was a middle aged woman working as Assistant Manager in an auto parts store (15 years). I not only grew up working on cars with my dad, but I also assisted my husband (for 21 years) who was a car, semi-truck, and farm equipment mechanic. I was an ASE certified Parts Technician. Yet I had to deal with men who, on a daily basis, couldn’t believe I knew what I was doing. They would go to a male sales associate, and then have to watch him come to me to find out what part was needed or how to test a part brought in.
My mother could no longer drive, so gave her car to my sister. Before delivering it to her, I, my ex, and my SIL (Son-in-Law) also a mechanic, went completely through the 6 year old car. We replaced the battery, brakes and rotors, water pump and thermostat, all belts and hoses, flushed and cleaned the radiator before refilling, did an oil change, new tires, etc. Verified heat and a/c both worked. Even put new wipers on it.
A week after she got the car, my sister called demanding $800 for “critical repairs”. Her (now ex) SIL had taken the car to a friend who determined that “no maintenance had EVER been done” on the car, and wanted money to replace everything we had just done “or the car wouldn’t make it a week”. I flat out told sis that her SIL and his friend were lying thieves. They didn’t appreciate me sending copies of all my parts receipts instead of cash…

BTW, it happens here on Quora too. I’ve lost count of the times guys have told me that stuff I’ve personally experienced/lived through couldn’t possibly happen because they’ve never had that experience. Shove it, dudes!