All SRS algorithm is expanding, i.e. increasing intervals. So maybe with continue success, it'll be: 1 day, 2, 4, 16, 40, 300 (arbitrary numbers).
How do you propose to lean medical texts, if without SRS?
Mnemonic techniques only work with rote recall, whereas flashcards, if formulated well, can help induction, understanding, not just recall.
I did study for medical exams with mnemonic techniques. Studies have shown that they do not inhibit understanding at all. In my experience they even help understanding. They totally dominate SRS on anything looking like a table or list. With text it's not as pronounced, but still you can memorize the key words, as few as possible, as many as necessary.
Flashcards are first of all a rewrite of the original material. If that is really necessary, the original material sucks, at least for the purposes of the exam. The physical cards are marginally easier to use than a textbook, but then again, writing them takes a lot of time and effort.
How you execute, whether with mnemonics or flashcards, is different.
With the umbrella term of "study or learning techniques", the learning schedule and execution are both included.
One big problem of SRS is that it gets unwieldy with larger chunks of information. SRS is good for vocabulary, bad for medical texts. The much bigger problem is that it takes an unpractical amount of calendar time. If you have three months, yes you can SRS a few hundred words. If you have a week and want full recollection at the end, you'll still repeat the list of words a couple dozen times and SRS makes no difference.
Another problem is the time it takes to prepare a database or a set of paper cards. By the time I prepare a database from a book I could probably read the thing twice or more times.
For exams that require recital of information (for example medical or law exams) mnemonic techniques like the Loci method (also called memory palace) are much more reliable and more practical.