I'm autistic (professionally-diagnosed) and haven't noticed this trend. Personally I'm used to being autistic and I wouldn't change it because it makes me me. That being said, it certainly wasn't something I would have asked for because it makes my life more difficult. There are a few advantages that make having it more manageable such as my close attention to detail but overall it's not something I'd recommend people wanting. People wanting ASD seems like a bizarre trend to me. Hopefully it's just a fad that will pass.