Yes in ideal conditions a faction would be more productive then a single player. But everything with players is case relative. Like lets assume each player is on for 2 hours a day. If a faction has 10 people they have 20 hours of work. Where as a player has 2 hours. But that often not the case. And it seems to me that most factions contain 3-4 diehards while everyone else on the roster is barely on once a day or even week. Where as a die hard player is often on and can accomplish much as they don't have to check with base-mates and discuss what to do. Their base may not produce as much overall to faction in terms of pure amounts,but a player with a good setup could best a faction in terms of each player to goods.
Factions also seem to get raided alot by either internal or external forces. Where as a player with an underground, hidden setup will probably never be raided. Like the "Sky Kin" a relativly new faction was recently raided.
A faction of well working members with a hidden setup where every member is loyal 100% would be ideal, but near impossible to achieve. But it is possible.
So in conculsion i feel that the question "Is a player better than a faction?"has 2 answers, yes and no. Yes they could easly produce more goods and get more profit as they don't have to split it. Yes they are alot safer from a raid. No in that they may not produce as much raw goods overall. It is a balancing act every player much choose. I have played both as a loner and as a faction member and they both are fun, but there is an undeniable sense of accomplishment when one can freely build and help others in a faction.