That is probably the obvious one, and a decent answer I'd say. Though it's always important to point out that segwit already increased the blocksize, both in practice, and even more in theory.

But the smallest change I'd accept while disagreeing is probably less impactful than that, like a slightly inferior version of a specific OP code upgrade or something. Kind of a boring answer though :)

0260378aef

bitcoin

What's the Worst Possible Change to Bitcoin You Would Accept? 

kilianbuhn

Let me go first: 

**Blocksize**. I disagree that blocks should be bigger. I don't think it solves scaling Bitcoin, I doubt it would increase the monetization of miners, I think current blocksize is enough to open channels.

But if I look back at where computer tech was 10 years ago💾 and imagine where it could be in 10 years - I would accept to use Bitcoin after a doubling or quadrupeling of blocks. 

Nowadays a raspberry pi + 1tb of hard drive are really cheap with a used computer almost free even... Quadrupeling to 4tb and used hardware in a few years would not be a huge deal. A 10x of block size or something would be catastrophic tho, that would be too much 😐