People walk in, see my wall hung with knotted ropes, and quietly decide they have come to the wrong class. I watch it happen most weeks. They look like equipment for somebody else.
It is the reverse. The ropes, like the blocks and the straps and the folded blankets, exist so that a posture can be done properly by somebody who cannot yet do it unaided. That is the whole idea, and it is the thing that separates this method from turning up and hoping.
Props are not a downgrade
Iyengar yoga holds postures for longer than most styles. Long enough for muscles to release rather than brace, which is where the change actually happens. You cannot hold a shape for that long if you are fighting it, and most people fighting a shape are fighting the last four inches of it.
A prop removes those four inches. The shape becomes available, you hold it, and your body learns something it could not learn while straining.
What that means in practice
Somebody with tight hamstrings gets a block, and reaches the floor. Somebody recovering from an injury works with a wall behind them and does the same posture as the person on the next mat. Somebody who has practised for twenty years uses a rope to go further into a backbend than their spine would otherwise allow that morning.
All three are doing the pose. None of them are doing an easier version of a class happening around them.
The uncomfortable part
Props slow you down, and being slowed down is not what most people came for. The first few classes can feel like you are being corrected constantly and progressing not at all.
Then, usually somewhere around the fourth or fifth class, a posture you have done badly for years suddenly has a floor under it. That is why I keep them on the wall.