Bill Kirchen has been using a pine Tele for decades. Pine body, pine neck, no truss rod! And it works, both tonally and structurally.
Pine can be rough and splintery when you use power tools. Not only that, you never know where a resin pocket lurks, covering all your blades with a sticky mess which obviously can be a problem in mass production. There's also a big difference in hardness between the lighter "summer growth" and the darker "winter growth" which can cause issues in leveling the surface. Then again, if you manage to get slow grown pine with very tight annual rings, it can be about as good as any wood can get.
As with any wood species it's not only about the choice of wood, it's also and possibly even more about the properties of the very piece of wood.