Been following Chris since I was 14 in 2008 until now in 2020. Got a medical degree in this time. Back in the day I was convinced that this whole thing was a very elaborate setup and that Chris simply couldn't be a real individual. Nowadays things make more sense.
Chris pretty much is a case study in the effects of cyber bullying in an individual with autism. It goes beyond my understanding why Bob did not simply forbid Chris from using the internet at all due to how clearly his psyche was being negatively affected by it, but then again, Bob also seemed to believe that Sonichu was genuinely famous? Strange situation but definitely poor parenting (You'll have to consider it parenting even though Chris was 20-30 years old at the time, since there never really has been any emancipation from the parents). Which honestly is a recurring theme all the way back to the mistake of getting Chris a diagnosis (good) but not pursuing therapy and support at any point.
Chris could've benefitted from such things in their late teens or even middle twenties. Even if the issues were ignored in their formative years, there would still have been room to remedy those. Chris might never have become a social butterfly even then, but a fairly normal life would not have been out of the question.
I'm in agreement with most people on here that Barbara has caused the most damage in Chris's life, however. The fact that she threatened with suicide and her own death on so many occasions, all for the motive of not letting Chris go, is so malicious and damaging. One shudders to think of what Chris went through in childhood - emotional violence and manipulation of children can absolutely result in just as bad if not even worse damage than actual physical child abuse.
I do not think that Chris qualifies for any psychiatric disorder outside of autism. The escapism/maladaptive daydreaming, imaginary friends/marriage partners etc can in my opinion all be explained by a combination of poor life satisfaction and having an elaborate autistic special interest (CWCville, OCs). Furthermore, issues such as escapism and paranoia, which both are present in Chris, tend to become more severe in situations of bullying. The fact that autism is in the picture means that it is hard for Chris to put the bullying and trolling into context - instead of perhaps looking into their own behavior as part of a larger social system ("Is there something I'm doing that makes me targeted by trolls?") , it resolves as feelings of helplessness. From this, it's not at all unreasonable to expect that a person with potential for escapism would spiral into such behaviors.
Chris's problems with believing that CWCville is real stem from the same root cause as his not having a good concept of death - abstract subjects are often difficult for a person with autism to fathom, especially without adequate therapy. A prime example of this is also the Father Call where Chris genuinely relates the death of a dog with somebody's mother dying.
There are issues with low self-esteem in there too along with poor ability to understand social cues which I believe most often manifest as problems with setting and enforcing boundaries and saying no. So many of the "sweethearts" should have alerted even a desperate person with how they spoke of private things that Chris hadn't told them personally (including literally quoting things Chris had said before they even came into the picture). There are so many of the chat logs/transcripts where I've just slapped my forehead and thought "Please Chris, for the love of god, say 'No!' or leave the chat/phone call!" on multiple points, but Chris has of course remained, receiving more blackmail and abuse in the process.
I have no idea of whether Chris truly has transsexualism or not, but I feel that the least one can do is show respect and not misgender. Claiming that calling Chris a woman is enabling of delusions does in my opinion become moot when you consider the amount of damage that has already been done.
Chris has a family and own history of heart disease, is at least overweight (been a while since I got a good look at body shape but would guess around BMI 30?), has at least had hyperlipidemia, consumes large amounts of sodium and has a sedentary lifestyle. And HRT. These all point toward a pretty high risk profile for severe cardiovascular events. It's at least fortunate that there's no habitual smoking involved, but I would not be surprised if there are more ER visits for chest pain in Chris's future 5-6 years. Around 40-45 is when you start seeing the effects of a poor life style on the heart and cardiovascular system.
When Barb does pass it is unlikely that assisted living or group homes will ever come into the picture because I don't really think that Chris is low functioning per se - there is knowledge of how to live responsibly but Chris often decides that other things are more important than such responsibilities.
Turned into a pretty long rant but this sums up my thoughts on Chris. Tl;dr - Autism, not schizophrenia, not disabled to motivate becoming a ward of the state, parents carry a lot of the blame but also the trolls and bullying, physical health will probably take a sharp turn for the worse soon, ignore/show respect for the transsexualism but don't mock it.