Here, in a nutshell, is why a lot of normal, non-technical users have trouble with FOSS...

They don't know anything about how and why Flash crashes their browser - or why Chrome handles it better.

They only know that their browser has crashed.

When someone more knowledgeable says "The problem isn't this, it's something else - so FIX YOUR COMPUTER before complaining" - well... the user just wants things to work, and their browser is still crashing.

Even if they had the time to dink around with their configuration until things were better, I don't think they're especially motivated in that direction. Most people don't enjoy messing around with their computers.

On the upside, your normal, non-technical user might not know enough to be offended by the PEBKAC remark.