No, I'm upset because I know people who have autism. My son has mild autism. Your comment was incredibly rude. If you don't want to own up to it, that's all on you, but when you use a word that's meant to describe a social disorder to imply that someone is mentally handicapped, it pisses people off. Honestly, when you use it in a negative fashion in general it pisses people off. Just be a little more empathetic to other people around you. You may not have used the word in an attempt to upset anyone, but using a word meant to describe a disorder negatively could obviously offend people. Unless you're honestly arguing that Asbel had a social disorder (which I'm not sure how you could possibly make that comment), your argument was honestly just ignorant. Just something to think about.
After reading your statement again I understand what you mean. I don't really agree that The Matrix sequels are comparative to spin offs since they were written before the first movie released (and quite honestly the Animatrix explains all of the confusion that the series creates if you watch it), but, again, everyone sees things differently. Highlander I completely understand your criticism.
I think Highlander is honestly worse than Tales of Symphonia and Final Fantasy X in that regard (because quite honestly the sequels make no sense according to the original storyline), but the comparison does have merit. Honestly I thought Final Fantasy X-2 wasn't a terrible game (though the pop star bit was pretty annoying, and the dress up barbie aspect took a bit to get past), but Final Fantasy X didn't need a sequel. Just like Highlander didn't need a sequel. Just like Tales of Symphonia really didn't need a sequel. So yes, I agree, they're basically spin offs that don't really affect the rest of the series.