Regarding "are microinverters really more reliable", the general consensus pretty much is they are LESS reliable, so the relevant question is the opposite: are they really less reliable, and if yes, by how much?
The bright side is that failure of one microinverter only brings that one panel down. If you talk to owners of microinverter systems, about every other has one failed microinverter, but it is not a disaster of course. Much more rarely you hear about string inverter failures, but when it happens, it's worse.
The often attributed cause for microinverter failure is the combination of worse efficiency (so more heat), fanless design, and exposure to elements, especially heat behind the hot panels, easily exceeding Ta=60degC, so it is harder to design them to be reliable. Yet, it is entirely possible to design super-reliable microinverters, just harder. String inverters tend to sit indoors in heated/air conditioned room temperatures.
The problem with getting information from contractors / installers is, everybody is selling their favorite systems, so information is always biased. IMHO, it's best to compare $/kWh and ignore technology differences, unless you have a system where every panel faces different direction with lot of shading, in which case you want microinverters.