When 2 redstone dusts was cut down, the dust without energy will back into single dust mode but the dust with energy will still be straight even another dust was removed.
MCPE-173814
Redstone Dust's Appearance Exchanges
Resolved
Invalid
0
(Unassigned)
Unconfirmed
iOS
IPadOS 17 beta 4
1.20.20.23 Preview, 1.20.20.22 Preview, 1.20.12 Hotfix, 1.20.13 Hotfix
Retrieved
All blocks that power redstone dust (lever, observer, repeater, comparator) make the dust align to the power source. You would get the same result as the end of your video by only placing the redstone block next to the dust. Placing and then removing the lamps has no effect on the end result.