Correct. What you are saying is true for almost all drugs: recreational doses are typically higher than clinical doses. Ketamine is the exception.
The recreational dose for a ketamine-naive user[0] is somewhere between 5-20mg. The clinical dose for depression is 86mg (not a typo), which is sometimes doubled, and the clinical dose for anesthetic purposes (which is what ketamine is mostly used for) is between 500mg-1g. The latter is IM injection, so it's also much more bioavailable than the first two (ie, the effective dose differential is even higher).
Of course, regular users develop a tolerance and heavy chronic users of ketamine can do more. But that's due to tolerance, not representative of the typical baseline recreational dose. (If they were to need ketamine for inpatient anesthetia, they would need absolutely massive doses for it to be effective).
It's hard to overstate how unusual ketamine is in this regard! It's very difficult to find an example of another drug that is frequently used both recreationally and clinically (by different groups of people) for which the standard clinical dose is 10x the standard recreational dose.
[0] "naive" is not a judgmental term; it's the clinical term used to describe a user who has no prior experience with the drug, or who has no baseline tolerance (ie, whose prior usage is far enough in the past that it is no longer relevant).