Not necessarily. That's how I normally smoke. But puffing quickly or too hard will cause your tobacco to burn too hot. If you find your pipe getting too warm to the touch, slow down your cadence, and sip a little lighter. You'll find what works best for you in time with practice.So short sips rather than long deep draws, even if they are slow.
Yet, it's the single most likely cause!Some people prefer the changed/muted taste of dryer tobacco, which is another thing altogether to making a blanket assertion that if your pipe smokes too hot it's on account of too-wet tobacco.