I have to agree: the magento ecosystem produced some of the worst code I've seen. we're currently supporting a few mid-sized online shops (40-80k products) - around 50% of our development time is spent patching things.

magento 2 has made things a lot better, at least on the tech side. but the 2.0 code is far from stable. even the now available 2.1 is hardly ready for production - unless you patch things up yourself or have a rather simple shop.