Sales is the gateway to money. Parent never said it wasn't important to build a great product, they said that even if you have the most amazing product if it doesn't sell there is no money coming in.
To your point, the goal of "trustworthiness" is to translate into more future sales.
Yes, product quality is important for two reasons:
1. A high quality product reduces the effort on the sales people. It’s nice when a product sales itself on quality alone and it’s also nice when sales can just bank on word of mouth marketing.
2. High quality products cost more to build but less to maintain, scale, extend. That results in predictability that is otherwise absent and expensive.
To your point, the goal of "trustworthiness" is to translate into more future sales.