TL;DR: The author asserts that Nintendo is able to be so creative because they retain employees long term rather than hiring and firing like other game developers.

Some excerpts that I found interesting:

All of the designers of the original Super Mario Bros. on the original Nintendo Entertainment System are credited designers on Super Mario Bros. Wonder.

Back in 2013, the late Satoru Iwata — the former president of Nintendo — said this at a shareholder meeting:

“If we reduce the number of employees for better short-term financial results, employee morale will decrease, and I sincerely doubt employees who fear that they may be laid off will be able to develop software titles that could impress people around the world.”