In my experience, the unqualified terms “consonant” and “vowel” unambiguously refer to individual letters, and the terms “consonant sound” and “vowel sound” are

In my experience, the unqualified terms “consonant” and “vowel” unambiguously refer to individual letters, and the terms “consonant sound” and “vowel sound” are used to refer to the noises produced when speaking. Thus, most people I know would refer to both “th” and “sh” as two consonants. This is coming from a general US education with no focus on linguistics, and feels like the sort of thing that may have significant regional variances.