I've recently discovered something is quite concerning for me, i.e. with Segwit transactions single block size will rise up to 4 Mb.
This would lead to a blockchain increase up to ~200 GB/year, while a normal laptop does not have more than 500 GB.
Right now blockchain is already at 200 GB.
It's something that the community spent a long time fighting about. As others have stated, we aren't actually using the full 4MB. Plus, the size of SegWit blocks are actually pretty reasonable considering that some of the earliest proposals about raising the blocksize were suggesting up-to-20MB blocks.
If LN will have a great development in the following years, and I hope I will. what about reducing block size back to 1 MB or even lower?
Since LN relies on being able to both open and settle channels on-chain, blocks can't be too small. Otherwise it could potentially cause issues with timelocks expiring if someone is spamming the blockchain. The increase SegWit provides was deemed a fair compromise.
Franky1 is a renowned troll and LN detractor. He despises SegWit and Lightning, so he occasionally makes shit up and hopes people believe it.