Haven't you realised that 'the second layer technology "Lightning"' aka Lightning Network is not Bitcoin and is an off-chain system and is centralised by design which contradicts and defeats the whole purpose of what Bitcoin was built for? [0]
The Lightning Network is decentralised because it is trustless and permissionless. Anyone can send Bitcoins instantly and almost for free. Check out the code to convince yourself.
[0] https://iopscience.iop.org/article/10.1088/1367-2630/aba062