I see more and more comments about community losing patience with Bitcoin developments.
then you are looking at 8+ months old comments.Quote
One result of it was the creation of Bitcoin Cash which increased the block size of Bitcoin but it seems it is not enough.
would you mind explaining how you came up with that conclusion? bitcoin cash currently has 8 MB blocks and they are empty (each block is 200 kB on average!) and how do you say it is not enough 
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I wonder why they did not created from the beginning a block size of 100MB, 200 or maybe 300MB? Why limit themselves to 8MB?
possibly because they were well aware of the dangers of increasing the block size to a huge amount all of a sudden. look at last months spam attack against bitcoin cash. it didn't cost a thing and it lasted more than week. blocks were full, transactions were delayed and you had to pay a higher fee if you wanted to get in a block (sounds familiar doesn't it?) and syncing becomes that much harder with bigger blocks. one of the problems with bigger blocks as OmegaStarScream said is the size and storage but also it is the usage of hardware when you have to use your CPU power to verify transactions (signatures).
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By having bigger block size wouldn't they fix the issues of speed and scalability...
yes it will fix it but only temporarily. Quote
I learned recently (here on a different post answered) that are concerns of decentralization as a result of larger block. What if somebody could solve the concerns of decentralization in a larger block? How valuable this will be?
there is a much better solution and that I called second layer which is basically what you keep hearing as Lightning Network.