Not necessarily. For example the “737 Next Generstion 800” is just known as the “737-800”. In some contexts it is further abbreviated to eg. “738”. For brevity the full name is not always used in all places.

I flew on a 737-Max after an 8 hour flight delay very recently and I thought they were joking when they announced what the plane was. I quickly looked up the stats on my phone (is this thing safe to actually fly?). It made the trip back more anxious than it had to be.