I cannot speak for their recent keyswitches, but I bought a Logitech mechanical keyboard a few years back and the switches started failing after a couple of years. Being able to replace keyswitches kept the thing running for a few months longer. Eventually I gave up and replaced the entire keyboard since it became clear this was a design issue rather than a manufacturer defect. Still, the ability to replace a broken keyswitch is a feature when paying anywhere from 5 to 10 times more for a keyboard.

Long story short: that mechanical keyboard was not the modern incarnation the tanks of years gone by. I am using one based upon Cherry switches at the moment. I don't have enough experience to judge the long term outcome, but my initial research suggests a similar outcome. Most of the hype around modern mechanicals seem to focus upon sound and feel (and, more justifiably, the ability to build your own), rather than quality. If that's the case, I feel that the gradual degradation of cheap keyboards is a more desirable outcome.