I can only speak personally about the career of an LCSW though I have friends/colleagues who are clinical psychologists and many friends/colleagues who hold masters level credentials as psychological associates, professional counselors, and marriage and family therapists. I'm also at an age (30, whoa) where some of my friends have settled into academia with clinical backgrounds/training.
Biggest rule here... the state in which you work will dictate licensing guidelines for each profession. Those can vary from state to state. The responsibilities of an LCSW in my state might vary from the responsibilities of an LCSW in your state. If you are concerned with your legal scope of practice in a potential field... use your friend google to refer to licensing statutes for each field and compare the notes.
As far as inferiority stuff... that's a feeling unique to the individual and you can only feel that way if you get caught up in the hype. In my state, psychologists aren't necessarily the "top dogs"... psychiatrists love to pull rank with the mental health clients and talk trash about the psychologists. The psychologists might talk crap about the social workers. The social workers might talk crap about the counselors. The counselors might talk crap about the family therapists and the family therapists will talk crap about the masters level psych associates. The clients might talk crap about all of them... regardless of training/credential.
Personally, I've experienced very little of the smack talk. I feel I've been respected by all levels of clinicians and academicians... but I've worked my arse off too. I've made myself present for research opportunities. I sucked it up and worked horrid community health jobs during a mental health reform in crisis. I KNEW my stuff and went above and beyond the MSW curriculum to learn about theory and application. I have met some jerk providers... but I went toe to toe with a psychiatrist my first year because I needed the client info to be heard, it had a good result, and I never looked back...
Now, all of that being said, I'm not in private practice full time. I prefer only brief interventions/crisis/assessment or group treatments. Even in my psychology-goaled life, I don't ever see myself becoming a star individual therapist. That isn't my interest. I know some truly talented LCSW private practitioners... who use "real" treatments as you mentioned below... I also know some horrible LCSW's who pretty much read from "Seeking Safety" for 9 out of 10 clients.
I wouldn't say that LCSW's are "practically" equal to psychologists in training or function. The roles are defined differently and the approach is different. Despite what I hear a lot on these boards, I've never experienced LCSW's trying to take responsibility from psychologists... in fact, I've seen much more of us begging psychologists to be more thorough in their part of the process so we can focus on our roles. I hope that has more to do with our failing mental health reform than an overall trend.
Similarities... both can practice indepedently, both can sit on insurance panels, both can join national membership/advocacy organizations with state/local chapters, both have to attend continuing education, both serve in academic settings in research/teaching, both can train interns, hmm... I don't know what else, I tend to only visit the board when I have a cold these days and my brain is fuzzy.
Differences... the testing part is huge because of the amount of effort that goes into understanding testing/assessment. Social workers are taught biopsychosocial assessment techniques where basically, you are just gathering information that someone else will use to medically diagnose the client (with your desired population, the severe and persistently mentally ill, they will almost always be on psychopharms). Psychologists (and/or psychiatrists), in my experience, will fine tune that broad assessment, picking out the important parts, testing and evaluating specifically as needing, and settling on a diagnosis that makes sense.
The pay is also different. Though you likely will have a hard time finding insurance reimbursements... Medicaid and Medicare reimbursement rates should be posted somewhere on your state dept of health and human services website. You'll likely see $20 - $100 difference per session as well as the psychologists have a greater "menu" of services they can provide for each client (and bill there after)...
I'm not sure what you mean by "real" treatments and might ask you to clarify... both psychologists and social workers will work in various settings and the treatments you will use vary upon site location.
I think you nailed it on the head with your disclaimer that this is an emotional rant. In the end, getting a degree because of what people might think... that's probably not the right reason to choose one over another. Neither program is going to be easy for sure... both difficult for their own reasons... and neither will be worth it if you aren't able to fully commit to this as a career.
Good luck to you. If you have any other questions, feel free to message me... I just got sick so I should be around at least a few more times before I'm well again. I don't like to publicly speak about my specific experience/training for privacy reasons but I'd be glad to share some in pm if it would help with your decision. For what it's worth, the MSW will not be my terminal clinical degree... I will be going farther with my formal education. Be well.