The more grippy a rubber's topsheet is, the more spin it can generate. If you are using a rubber with a very grippy topsheet that can create a lot of spin and you just put the racket out on a ball that is coming in with a lot of spin and you don't quite know what the spin is, then, you might feel a rubber is spin sensitive and the ball shoots out in all sorts of directions you did not anticipate. As someone above said, if you have that same grippy topsheet but it is now on a harder sponge, that will add the element that you will need to be more precise in the depth and quality of your contact, so, the harder sponge takes more skill to utilize. Therefore, someone who is just putting his racket in the way of the ball will feel more of that "spin sensitivity" effect that causes the ball to do funny things when you have not read the spin properly.
However, a player with decent skill who knows how to read spin can either adjust the angle of the racket and meet the spin in a way that counters the spin and uses that spin to the player's advantage. Players who use a traditional penhold BH can be amazing at what I just described and it is worth watching some of the magic they can do in how they touch the ball when returning wacky spin from an opponent's serve.
But there is also this other thing. If a ball coming at you has nasty spin and you have read the spin remotely accurately, if you contact the ball tangentially (brush contact) and you have good racket speed, and you control the depth of the contact, and you choose to contact the point on the ball where the spin will have a smaller effect (near the axis of the spin) that rubber will just do what it does as you add your spin to the ball and if you have the skill to do that, the rubber should not feel anything remotely like what the term "spin sensitive" implies.
And if you do the same stuff I described above, but choose to contact the ball where the spin will be strongest, you can give the opponent back a ball that has
MASSIVE spin. And it should still not feel like the rubber is spin sensitive. You just will need enough bat speed and a useful depth of contact to take the opponent's spin and do what you want with it.
So, when you learn that you spin the incoming ball, no matter what the incoming spin, issues of spin sensitivity may not even be things you remember exist.
And if you are in the learning phase where you don't know how to spin through the incoming spin, whether taking the path of least resistance, most resistance or anywhere in between, then rubbers that are more middle of the road, that generate a little less spin but are not likely to cause you to fear the incoming spin, those would be worth using because they will help you learn how to spin the incoming ball with less of the emotional stuff that could happen to someone who keeps wondering why his attempt shot off to the left, the right, hit the ceiling or hit the table before it got to the net.
