Japanese shipyard capacity for super-battleships

Could Japan have expanded enough shipyards for many Yamato-scale ships?

Possibly, but only through costly infrastructure investment and trade-offs with other spending, while addressing earthquake risk.

Only a few Japanese yards could handle very large hulls, while expanding that capacity would demand major investment in land and earthquake-resistant infrastructure. The expense would compete with army and other national spending. Building super-battleships in more yards would also make the programme harder to conceal, although construction of large merchant ships could provide some cover. Yard capacity was therefore an industrial, fiscal, and security constraint rather than a matter of slipway size alone.