For signature\heuristics-only protection this comparison is generally correct... as that is what the labs are actually testing.
However, the labs do not evaluate other protections - such as firewall, behavioral monitoring, anti-exploit, host intrusion prevention system, etc.
Some AVs have these features, others do not. Labs follow testing methodology to allow for consistent, meaningful comparison between AVs - so they test scan engine - which each AV does have.
At least that is my understanding from reading the various test lab methodologies and AMSTO guidelines.
For better or worse - Everybody likes ranking lists - whether it is cars, toaster ovens, universities or security softs. And everybody likes a winner.