There are two important caveats. First, hard-to-fill high-skilled jobs do not always require many years of post-secondary training. Even among H-1B visa requests, about 25 percent are for occupations that typically require only an associate’s degree, meaning that the current U.S. workforce could be trained to do these jobs at relatively little cost. Second, not all STEM jobs are experiencing the same symptoms of shortage."H-1B Visas and the STEM Shortage" By: Jonathan Rothwell and Neil G. Ruiz
Now let's look at the occupation definitions that are valid for H-1B Specialty occupation.
(i) “Specialty occupation” defined
(1) Except as provided in paragraph (3), for purposes of section 1101 (a)(15)(H)(i)(b) of this title, section 1101 (a)(15)(E)(iii) of this title, and paragraph (2), the term “specialty occupation” means an occupation that requires—
(A) theoretical and practical application of a body of highly specialized knowledge, and
(B) attainment of a bachelor’s or higher degree in the specific specialty (or its equivalent) as a minimum for entry into the occupation in the United States.