I am really not sure if this is intended behaviour, but since redirecting it by placing another piece of dust does affect them, I would assume so.

INTENDED BEHAVIOUR:

when you redirect a piece of redstone dust by placing a block on top of it, thus breaking its connection to an adjacent piece of wire diagonal to it (next to it and one block higher, connected vertically), any adjacent redstone components like lamps, pistons or trapdoors, should power or unpower accordingly.

CURRENT BEHAVIOUR:

It doesn't do that, so you can have a piston being powered by nothing, or a trapdoor that should be open but isn't

REPLICATION STEPS:

Honestly, best way to describe the bug and steps to replicate it is visually, just follow the screenshots (I hope they upload in the correct order)

Step 1: place two bits of redstone, a powerable block (that doesn't redirect wire like repeaters do) and a power source.

Step 2: block the connection between those two bits of redstone

Step 3: observe how the powerable block doesn't get powered even though the wire is running right into it. Updating the component by BUDding it makes it powered again.