That isn’t a PT plot hole, it is an OT one. Unless you just chalk it up to him lying.
How is that an OT plot hole?
When do you believe Anakin Skywalker told Obi Wan “please give this to my son when he is old enough”? Was it before or after he was hidden from his father at birth, per Obi Wan in ROTJ?
ROTJ only suggested that it was a potential plot hole, since it’s entirely possible that Anakin discussed his plans for the future with Obi-wan, even if he didn’t know for sure that he would have a son. The prequels confirmed it as a plot hole by not having this conversation, so it’s partly the fault of ROTJ, partly the fault of ROTS.
How does that even work? “I’m off to be evil now, Ben. Here is that lightsaber I always wanted to give my son I don’t know that I have. I won’t need it now, I’m building a red one!”
The plot hole is that Vader was not Luke’s father initially. He had no job after ANH per Lucas in Splinter. Anakin and Vader were different people. To fix this, they just made Obi-Wan a liar. It works really well if you see Obi Wan as a liar trying to get Luke to take the heroes journey.