How to recreate: Build a powered Redstone line that goes over a copper bulb and you will see on the downward side the Redstone goes to level 0. This does not make sense since the Redstone wire is powered when going up but not when going down.
Linked issues
duplicates 1
Attachments
Comments 3

They weren't talking about redstone lamps being powered by adjacent copper bulbs but rather redstone dust loses its power when the power is traveling down a copper bulb.
(Edit): look at the photo submitted it clearly shows what I said. This is a issue that needs to be fixed.

The "duplicate" ticket you are saying is resolved is not related to this ticket.
Thank you for your report!
We're tracking this issue in MC-266125, so this ticket is being resolved and linked as a duplicate.
That ticket has already been resolved as working as intended, which means this is not considered a bug and won't be fixed. Please do not leave a comment on the linked ticket.
If you haven't already, you might like to make use of the search feature to see if the issue has already been mentioned.
Quick Links:
📓 Bug Tracker Guidelines – 💬 Community Support – 📧 Mojang Support (Technical Issues) – 📧 Microsoft Support (Account Issues)
📓 Project Summary – ✍️ Feedback and Suggestions – 📖 Game Wiki