Once people are reluctant to spend then, the economy will stay depressed because, people expect deflation AND deflation will continue because the economy remain

Once people are reluctant to spend then, the economy will stay depressed because, people expect deflation AND deflation will continue because the economy remains depressed. Please correct me if I am wrong, but isn't the value of the total money supply supposed to equal something like the total value of the goods and services in the economy that that money supply represents (not sure if the wording is correct but hopefully I got the idea across). If that is the case, then won't a decrease in spending cause the total value of the money supply to decrease, meaning the expectation of deflation will cause some amount of inflation, such that the system stabilizes? Because of this, I don't see how you can have a deflationary spiral in a depressed economy based on anything other than speculation (and thus a Bitcoin bubble which will eventually pop). I do agree that Bitcoin is naturally deflationary; if there is economic growth, the money supply can't expand to keep up. And Bitcoin's deflationary nature slows this economic growth. Thus, I think that Bitcoin will eventually reach a stable real value. I think there must be a flaw in this reasoning because I'm sure many economists would disagree but I can't seem to find it myself.