It depends on the vehicle. I weigh 400 pounds, and the seat in my Mercedes M class (now GLE) is in perfect shape, none the worse for wear and tear after 11 years and 180.000 miles. By contrast, the driver’s seat frame in my 2 year old GMC pickup is ‘loose’ and the back cushion is not properly aligned with the seat cushion.
This thread reminds me of my beloved and dearly missed “dad”, (not by blood) who was 6* and around 350 pounds and drove a -69 fiat 600 as a daily driver. Around 1 year of use would cause the seat brackets to go through the floorpan and I had to get them back in place. After doing this for 3 consecutive years, I welded 4 pieces of 0,5 inch tubing across under the floorpan under the seat bracketts. Job done for many years after.
I had a 2005 Chevy van, well my 290 lb. hubby wrecked that seat. Now I have a 2012 Escape. I sure do miss my van though as it had lots of storage and the Escape does not have much storage. Nice little vehicle but now I am worrying about him driving it. We also have a F-150 and boy that is a great vehicle for storage and comfort. He also can’t wreck that seat. I tend to have a vehicle for long term so hoping for the best this time…lol