You can easily store the blockchain (which is mostly historical data, ie. “empty accounts”) on an old (rotational) HDD because you access it in a sequential manner, which is fine for old HDDs. It’s only the set of “non-empty accounts” (unspent transaction outputs in technical terms) that you need random access to. But this data can be stored in RAM since it’s only about 3.5GiB.

Anything over 40 GB is impractical for wide-scale distribution that would create a healthy network, and really anything over 2 GB is problematic and will have a much narrower reach.

This is evidenced by the fact that almost no one these days actually runs a local wallet. The number of logical nodes has decreased while the number of wallets has dramatically increased.

Who has ~250 euros (excluding the machine this SSD has to be in) to drop on a random hobby?