If I was a miner, I would think long term and realize that I would end up raking bigger fees once bitcoin goes mainstream thanks to lightning network allowing for trillions of transactions daily
Their thoughts are like, "I will support this preferred scaling solution because it might result in the price going up and me getting temporarily higher profits", or "I will support this preferred scaling solution because it might help Bitcoin to retain its market dominance".
At this point, it's more like desperation to just clamour to finally do something, rather than thinking about the fees much. Fees are useless if they don't actually end up receiving them.
As lightning networks transactions go up, potentially reaching global adoption with trillions of transactions daily, all those transactions will ultimately go into the blockchain and get processed by miners, so the overall miner revenue will be higher than just some rich people trading onchain.
Encryption & cryptographic functions always slow things down.
Whether its a WIFI router or bitcoin, it could be guaranteed that it will always be somewhat slow.
Not if miners enable segwit to get 100% functional lightning network.