Not a bitcoin maximalist per se(though a huge majority is BTC), a shitcoin is simply a coin/token that is either:
1. Unnecessary: A perfect example would be Dentacoin. A coin for dentists? wtf?
2. A scam or a pump & dump: No explanation needed honestly. e.g. Verge(XVG)
And I fully agree. Shitcoins are there just to make things cloudy and shitcoin developers are existing or doing their things for the sake of getting money or remunerations as their contributions are not needed that much. Shitcoins who are scams are usually victimizing innocent people -- people who just desire to get something of what they investing. We have to be careful with any project that we go with...as many of them are just shitcoins masquerading as the next big thing in the world of cryptocurrency. Beware!