This is true (the royalty varying on the size of the memory) but the royalty was also significantly higher if there was any custom hardware involved on the cart - specifically because you actually had to purchase the "Game Pak" from Nintendo, so they would charge you "whatever they could get away with" for enhancement chips.

Any idea if Enix was locked into buying the Game Pak already for Star Ocean by use of battery-backed SRAM or not?

All the game paks (aka cartridges) were manufactured by Nintendo. By selling a licensed game, they were already locked in.

So it's just a question of "was the S-DD1 priced cheaper than another (or larger) ROM chip by Nintendo" right?

I remember Street Fighter 2 being something like $69 (in ~1992 USD) when it came out, and it was something like 16 meg. A 48 meg ROM would have easily been $100+ if not $150.

Fun fact, an inflation calculator says that in 1992, a 50 dollar video game cartridge would be equivalent to $92 today. DLC and terribly unethical video game publishers aside, for the non-piracy crowd, we live in a golden age of affordable video games at $20 to $35 each.

If you can be content with buying xbox one and ps4 games on ebay a little while after they're released, you're unlikely to ever pay more than $20 for a game.

Yeah. Consider that the MSRP for the original legend of Zelda for the NES was $49.99 in 1986. This title took a team of ~7 people ~2 years, and several team members spent 5-7 months of that time also working on Super Mario Brothers, so it would probably have taken less time if not for that.

The typical price for the modern AAA title in 2019 is still only $59.99. These games will have 30 or so people at the absolute minimum and having well over 100 people is not at all rare. They often take 3 years or longer to make.

Even if you don't take into account inflation, such a small increase in nominal price despite enormous increases in development cost is rather remarkable. Then if you consider that inflation means that the real price of AAA games is basically half of what it was, and B list games being about half of that yet again...

Honestly I'm not surprised by DLC and microtransactions. The normal list price of AAA video games is substantially lower than it it should be. My gut tells me that in most other markets, the price would have risen to at least the $80-100 range, if not more, even taking into account the much larger sales volumes these days.

Yeah well back then game development was hard as it required deep knowledge of the hardware and also high critical thinking to implement various software tricks to overcome the limitations of the hardware. Those devs were as close to wizzards as you could get.

Later, hardware resources became cheaper and less of a concern and the SDKs made development a lot more accessible to people who didn't have a master's degrees in EE so the workforce could be cheaper and plentiful, cumulating to the game industry becoming the sweatshop it is today.

I don't think its got anything to do with game development being hard. Spectrum games were hard to develop, but games were cheap(er) and easily copyable, and one company didn't have a monopoly on production, I assume the same dynamic existed for the C64 also.

I suppose you could make the case that game development is always going to be hard, people are always going to push the abilities of the platform etc, it isn't like todays titles are tossed out on a weekly basis.

High margins combined with more customers causes this to make economic sense as the dev costs are spread across more customers.