Every syllable has either a vowel or a sound that acts as the locus of a syllable.
Y, which is often a glide, can become the locus of syllable, as can several other sounds that are more often consonants. Those would be: laterals (r, l) or nasals (m, n, ng) (e.g., rhythm, nation, and some lax pronunciations of closing -ing, as in ‘talkin on the phone’.)
W, a glide that’s often similar in function to y, can also become syllabified in extreme cases, such as when one affectedly makes ‘cow’ have two syllables.
Some pretend that syllabic r or l (e.g., father or gutteral) are preceded by a schwa, but that view obfuscates what’s really going on, IMHO.
My linguistics degree is from the University of Illinois.