All the current challenges facing Bitcoin as regards to Block size/Segwit are clear indication that Satoshi never anticipated a highly successful Bitcoin in a short time.
this might be the case. but we don't know satoshi's true vision for scaling. he did, in one post, say that we
could increase the block size if needed (and laid out a way to do so). but from reading his posts, i don't think he was thinking particularly hard about this aspect of the system.
i think he hoped that technology would progress fast enough that scalability wouldn't be such an issue, but he didn't stick around to find out. as it is, even 1MB blocks are a threat to the decentralization that is supposed to underlie the system and allow for trustless transactions.