I think it depends alot on the baseline mentality of the indivdual as well as what you use and in what setting. There are lots of beneficial research on psychedelics for treating various conditions, and they really have the potential to elevate your mind to see your problems in a new way - perhaps granting you a new perspective that can help you solve or deal with problems much better than a mindset that is stuck in routine-negative thinking. For a lot of suicidals and people with depression, there are often strong negative biases and thoughtforms that have developed over many years, that constantly go on in the subconscious mind. There is also perhaps untreated traumas and experiences and all of that. There's however a lot of promising studies done on this; everything from MDMA-assisted psychotherapy against PSTD to ketamin for treatment-resistant depression, to psilocybin against the fear of death in cancer patients. It all comes down to your indivdual needs; how you do these things (under what inner and outer conditions) and how you work with what comes to the surface.
There's often adviced against the use of psychedelics for people with a history of psychosis and similar mental states, probably because they can really challenge and shatter your views of yourself and reality, and a mentally strong baseline is often crucial to deal with that. It's also often adviced against taking them in particularly challenging seasons of your life (like shortly after a break-up, or other personal events that affect you deeply).
So, I'd say, if you would ever consider this - do your research on it, carefully decide and use it in a proper and wise way. Give it due respect, as this is definitively not something to play around with - it's potentially extremely powerful that can alter your mind in fundamental ways. Can it provide you with a newfound appreciation of life along with meaning, happiness and purpose? Definitively. Can you be absolutely certain that they will improve your life and not give you new challenges instead? Probably not.
I can recommend the Michael Pollan series 'How to Change Your Mind' - they are quite good. Also I see some other claims here that are incorrect as far as I know. Psychedelics in general have extremely low chances of addiction (unless you consider ketamine and MDMA/ecstacy as part of of psychedelics). Also if you are on SSRI medication, that can create problems (serotonin syndrome) with MDMA, but studies have not found this to be the case with other psychedelics from my knowledge. They are likely to make it much less effective though, as SSRIs will downregulate the 5HTP-2A receptors to prevent the reuptake of serotonins in the psynapses. Psychedelics are targetting these exact same receptors. You must therefore either take a greater dose (you should gradually up the dose to find out what works for you since people are reacting differently individually) or chose to tap off the SSRIs (should only be done under medicial supervision). Above all, be careful.
