I think that what you describe is a simple case of the known vs the unknown.
I.e., there's no particular reason to assume that the EV will develop a fault or that the battery will need replacing under warranty, it's just that the latest breed of EVs have only been on the market for 3-4 years and it's too early to tell what their reliability will look like long-term.
My own view is that a vehicle based on an electric motor and a battery is inherently more reliable than a car equipped with an ICE engine and transmission, however the ICE engine and transmission have been in development for decades so they do have that advantage.
Being in IT, I remember how unreliable were the Seagate 10mb and 20mb HDDs back in the eighties, but after 30 years for manufacturing millions (if not billions) of these complex and delicate electromechanical devices, the industry managed to reach very good reliability and very high MTBF (for the commercial drives anyway).
In comparison, the first SSDs on the market had small capacity, were expensive, and very unreliable.
But 10 years later, SSDs have now overtaken HDDs in reliability. However, HDDs are still outperform SSDs in price-per-gigabyte, mainly due to the fact that the industry has been making them for decades now.
I believe that the same applies to ICE cars, any advantages they currently have are mostly due to the fact that we've been making them for over a century now, and we got the process down to a tee. We're still finding our feet when it comes to EV manufacturing.