Are you talking about current storage or future theoretical storage?
Because your examples seem a little stretched to me.
124GB growing 100x is 12.4TB, which is more than what most people have available at home, so I wouldn't say it's "easy for anyone to keep a copy".
124GB growth 1000x is 124TB, which is definitely out of reach of any normal person right now, so I wouldn't say "it wouldn't be much of a problem to keep at home"... Even at the sweet spot of a 4TB HDD, that's 31 hard-drives, or about $4,000 of HDDs, plus the NAS enclosures, plus probably redundancy, which is many other thousands depending on the RAID scheme. So we're probably talking about close to the price of a small car just to store a 1000x larger blockchain.
As for a million times bigger than 124GB, that's definitely not that easy to keep a bunch of distributed copies among miners everywhere with anything close to current technology.
Maybe I misread, or misunderstood what you said, but I was thinking that the multiples of 124GB you were talking about didn't seem that small to me. Maybe you were thinking about theoretical future storage capabilities...