Please read that link you just posted, it supports my statement 100%. Also take a look at the "talk section" and you will see that there are several people criticizing the biased presentation of MWI's popularity, eventhough it clearly says the vast majority rejects MWI. so it's even wose than presented. Next time read your own sources before using them to advocate for your own position.
Also the fact that there are several people who consider MWI to be a nice mental model to use while doing physics, but ultimately not the fundamental representation of reality, these people will often vote "yes". This is the reason for Tegmark sometimes starting his presentations by taking a poll of the audience and then go on to say "now out of those who support MWI, how many believe these worlds REALLY exists and this represents reality?" Then usually quite a few takes their hands down and no longer should be counted as "pro-MWI", Martin Gardner explains this somewhat in the link you gave above...
Lastly there are yet 2 more factors affecting these results, when a proponent of MWI decides to take a poll, it is highly likely that his audience is not a nonbiased random sample of the physics community, it's highly likely that other MWI sympathizers show up to his talk because they already share his views. This is why it's always emphasized that it is a "highly unscientific poll"
Last but not least you've got to realize that there are somewhere around 10 different Many worlds interpretations and 5 different Many Minds interpretations, all of these people would say "yes" when asked "do you support MWI?" when in reality they are not in agreement on very important details at all...
The subject has already been raised in this thread, but in a clumsy fashion. So here is a fresh new thread, where we can discuss, calmly and objectively, the pros and cons of the "Oxford" version of the Many Worlds interpretation of quantum mechanics.
This version of MWI is distinguished by two propositions. First, there is no definite number of "worlds" or "branches". They have a fuzzy, vague, approximate, definition-dependent existence. Second, the probability law of quantum mechanics (the Born rule) is to be obtained, not by counting the frequencies of events in the multiverse, but by an analysis of rational behavior in the multiverse. Normally, a prescription for rational behavior is obtained by maximizing expected utility, a quantity which is calculated by averaging "probability x utility" for each possible outcome of an action. In the Oxford school's "decision-theoretic" derivation of the Born rule, we somehow start with a ranking of actions that is deemed rational, then we "divide out" by the utilities, and obtain probabilities that were implicit in the original ranking.
I reject the two propositions. "Worlds" or "branches" can't be vague if they are to correspond to observed reality, because vagueness results from an object being dependent on observer definition, and the local portion of reality does not owe its existence to how we define anything; and the upside-down decision-theoretic derivation, if it ever works, must implicitly smuggle in the premises of probability theory in order to obtain its original rationality ranking.
Some references:
"Decoherence and Ontology: or, How I Learned to Stop Worrying and Love FAPP" by David Wallace. In this paper, Wallace says, for example, that the question "how many branches are there?" "does not... make sense", that the question "how many branches are there in which it is sunny?" is "a question which has no answer", "it is a non-question to ask how many [worlds]", etc.
"Quantum Probability from Decision Theory?" by Barnum et al. This is a rebuttal of the original argument (due to David Deutsch) that the Born rule can be justified by an analysis of multiverse rationality.