Do you think we can make a good enough 2D animation inside adobe Photoshop?

Yes you can do any2D animation inside Photoshop, but it will be limited to some features. you will not be able to use camera, pegs or cell painting features.

we can do an enough2d animation as a gif animation as in adobe family we have adobe flash help us more to be comfortable by our animation  

Yes we can do a better2D animation in Photoshop.