Satoshi had no limit on block sizes at all.   From block 1 it was legal to have a 2MB, 20MB, even 33MB block.   There was a 33.5MB limit on message length and since blocks are transmitted as a single message it would have limited blocks to only 33.5MB but even this wasn't a hard limit as new message type could have been added which transmitted blocks in other ways (i.e. header & txn hashes vs full transactions).

The 1MB "limit" was added as a temporary anti-spam measure 18 months later.   There was no voting, no significant discussion, and the commit wasn't made by Satoshi.  It actually was combined with a bunch of other unrelated changes and not even well documented at the time.  There is nothing which indicates this was a core design decision that Bitcoin would perpetually be limited to 1MB.