It had to be a horrible experience for him since for sure he was familiar with other BASICs. One example: Prior to Pirates!, in 1982, Sid Meir made a game called Chopper Rescue in Atari 800 BASIC:

https://www.mobygames.com/game/41499/chopper-rescue/

https://www.youtube.com/watch?v=rUyebYD5UO0

C64 BASIC had to be a step back, but that's where the sales were to be made. For example, in Atari 800 BASIC variables were not limited to two characters.

C64 BASIC was really PET basic from ~1976, very close to Microsoft's Altair BASIC.