in this video Lane talks about opening up Coda for pack makers. This they can only do if the performance goes way beyond what we have today. So I am rather optimistic on this issue.
Just have in mind what it took to “Design the BELLMAC-32 microprocessor on a 20x20 foot printout” and imagine where we are today
As this topic is the first Google result for “coda page size limit” I’m adding a link to the official documentation about “Keeping your docs within the size limit to use with Cross-doc, Zapier, or custom API integrations.” The mentioned limits are 10,000 rows and 125MB. More details: Are there any size limitations on docs accessible via the API? | Coda Help Center