I've always had the opposite problem. Users were willing to pay, but I didn't have a good enough user acquisition funnel to justify it so it shut off payments.
It took me a while before figuring out how to get to 1000, then 10000, then 100000, but user acquisition and retention are imo the hardest things for a first-time product maker.
I actually think monetization is easy once you have the user base unless your product inherently does not provide any real value.
I bet anything that 99% of startups fail due to traction, not inability to monetize.