Good, why? I haven't seen this adequately explained. Considering we are not even reaching capacity at 1MB, 8MB is completely arbitrary. 8GB is beyond arbitrary -- it's simply out of touch with reality. The only possible justification is Moore's Law, and as I pointed out above, this is an illogical and unscientific basis to go by.
no one can see in the future. this means we cant know how much blocksize we will need. but we can make educated guesses about what might be a good max. and if we are wrong with that maximum lets just have a little trust in miners which dont want to let bitcoin fail to choose some reasonable value.
yes 8mb is arbitary. but why is this a problem? it is not possible to calculate the future (at least for now and not from inside our universe). what transactions are put in a block and which arent is a decision made by people who have the incentive to keep this system running.
And why do we need to determine the max block size 20 years out? Indeed, it's impossible to make logical estimations about future transaction volume..... so why invent an arbitrary number and just go with it?
Block capacity is connected to transaction volume growth. So we have real world data to estimate our capacity needs for the foreseeable future. And those simply don't line up with 8MB or 8GB. Maybe in the future they will.... maybe. We can cross that bridge when we come to it. In the meantime, the emphasis should be on consensus. A conservative approach that scales to real-world needs rather than fantasized ones based on Moore's Law is much preferable in that regard.
Six years in, we have not hit capacity. Why are we planning on 8000x capacity 20 years from now? Just because? Incredible lack of foresight, and quite audacious to assume that we have every possible technical problem that may arise figured out, today.