Decentralization is always the highest priority for core. Increasing the block size directly threatens that this since it highly favors the larger miners.
That ship sailed a loooong time ago, when the first ASIC went to production.
But wouldn't larger blocks make it more difficult to run a node? The chain would grow too fast.
Absolutely, long term its not a great solution. However its not an immediate problem for existing full nodes (they'd increase new blocks). Today the immediate and major problem is blocks are full and fees are high. Fix the block size later. Or we can continue to do neither, let the BCH option gain momentum.