That's their reputation, but it doesn't always stack up in reality.
Recent example: https://twitter.com/levelsio/status/1600316372344373249
Canonical HN example: https://news.ycombinator.com/item?id=30535572
The association of Stripe with simplicity and good dev experience could be more due to Stripe's marketing/PR than the views of devs who've used Stripe APIs, at least from the few things I've read.