Switches can certainly fail, with potentially dire consequences (see the Apollo 14 abort switch failure). I would assume the number of failure modes for touch-based interface hardware are vastly more.
Touch controls are, no doubt, easily reconfigurable, which is probably great for profit margins. The idea of the human spaceflight industry applying "cost down" mentality to crew vehicles scares the heck out of me (and I'm not even flying in them). (I'm thinking about the Boeing MCAS mentality, but for spacecraft...)
Wonder if reliability of virtualized controls surpasses the one of dedicated hardware though.
I suspect one of the reasons Apollo computers were all built with just one type of logical chip is the ability to replace faulty parts - one just need a single type of replacement. If for some reason touchscreen malfunctions, what options are left for the crew?
First, the spacecraft is I believe fully automated. While there is the ability to pilot the craft manually using onboard controls, my understanding is that is already considered a backup or unusual scenario.
As far as the touchscreens themselves, my understanding is there are four touchscreens total, and each can represent / control every aspect of the vehicle. So if a single touchscreen fails, the other 3 provide redundant access to necessary controls.
Finally, the dragon capsule does have manual (non-touchscreen) joystick controls for the critical flight controls.
So these systems have enough redundancy that a touchscreen failure should absolutely not jeopardize the flight.
Joysticks are better, though some convenient indication is also required (the "screen" part, not the "touch" part). I'm sure the designers saw questions like that; I'm just curious about details.
The Apollo Guidance Computer was built with two types of chips: a 3-input NOR gate and a core memory sense amplifier. The reason to use just one logic chip was because ICs were very new at the time and there was very little reliability information. By standardizing on a small number of components, they could procure enough to determine and maintain quality. (See Journey to the Moon chapter 12.)