I expect him to make more of an impact this season and yes, I think there's been actual improvement.
Naturally certain game conditions will suit certain players. I've never said Sissoko was anything more than a 6-7/10 on Saturday and I've acknowledged multiple times he's going to be better starting deeper.
But it's the level some people (not even you) have gone to to belittle one of their own players. If it was to his face, it would be bullying. It isn't, but it isn't really balanced criticism either. As I've said, some players get away with poor performance after poor performance, but if they fit certain criteria, Spurs fans collectively (e.g. On a majority basis) give them an easy ride. Hard running or look pained when you miss a chance? Yep, you'll be fine despite 6 months of no performance. A silky player that hasn't scored or assisted but has done a couple of dribbles here and there and turns and faces forward well enough? Yes, no matter how little an impact he is having, he will get time.
Players that rely on their physicality in an attacking sense? Hard luck. A silky player can draw admirers from a Spurs crowd and get patience because they've shown a classy turn here or there. A Jenas or Sissoko gets no credit for a lung busting run even in a patch of bad form, no excuse made for them that patience is required (collectively, on a majority basis) because they've gone some small good points, because their face just doesn't seem to fit.
Sissoko was signed precisely because he was different to the other players we had. He is going to have his own strengths and his own weaknesses. But after a good game, you still get people tearing down his performance, picking it apart minute by minute and touch by touch, and claiming he is the worst one out there. It cannot be denied that no other player faces a similar negative atmosphere around them, and unfortunately this same attitude appears in the stands so it isn't just an online thing. It doesn't help.