I think its important to match interview style with the company. If you're a very theoretical data-oriented / machine learning company then knowing algorithms and computer science is very important so traditional coding tests are probably pretty important. On the other hand, there are times when all you need is a capable Software Engineer with experience and knowledge of a particular tech stack. In that case, whether or not he paid attention in algorithms is not going to give you a great indication of whether he can work full stack.