boats are pretty much useless in this game so can it be possible to fish from them? since sometimes you cant reach fish from the shore.  

This idea was brought up before to make boats more useful. But I don't see anyone taking this idea into consideration yet.  

When this was discussed before the realistic answer was that this would be considerably difficult to code aswell as there being much more important projects in development.  

Well, I can see it being difficult to add in a function on a boat, since that it's already difficult enough to code the fishing mechanics. Maybe at a later time I suppose, once they've already completed all of their important projects like Crafting and the Holiday Events.