I think it should be available but not compulsory.
ds2 is 2.9 and has had to be restricted to 1 hour a day on the computer. I initially had reservations as well but he has learnt skills and words from playhouse disney and cbeebies that have enhanced his social interactions.
he knows what objects and numbers are and loves saying 'good job','we did it', 'I'm the winner', 'don't worry mummy. i'll find it', 'shall we try it gain?', 'this is for me and this is for you', 'shall we try it gain?' and my personal favourite 'stink, stink, stink' (think, think think from my friends tigger and pooh). He tends to repeat what is said by his fav characters and the storylines seem to be transferable to his social life and daily routines so I think it has enhanced him. ds1 however can't be arsed and is only just getting to grips with watching some dancing alphabets on a sesame street program.
We've found programs teaching actions, rooms in the house, daily routines, problem solving, painting and decorating, collage, jigsaw puzzles, matching, construction etc. The computer is the new weekend babysitter when i have chores to do but ds2 manages to insist that we join him and applaud whatever he's doing from time to time.