Let’s look at the actual survey results.
First, the survey asked Muslims in Muslim-majority countries (plus Russia and Thailand) whether they thought shari’a law should be the law of the land (or, in the case of Russia and Thailand, of the Muslim regions within the land). Note that that entirely excludes, for instance, the more than 10% of all the world’s Muslims who live in India.
Majorities in most of the countries surveyed agreed with making shari’a the law of the land. (However, among those who agreed, majorities in most countries said that shar’ia ought to apply only to the country’s Muslims, not to all its citizens.)
The survey then asked only the pro-shari’a respondents in each country whether they favored the death penalty for apostasy. Majorities of those respondents responded affirmatively in Malaysia (62%), Afghanistan (79%), Pakistan (76%), Egypt (86%), Jordan (82%), and the Palestinian territories (66%).
Now all we need is to do the math on those subsets of subsets.
Malaysia has about 1.1% of the world’s Muslims, of whom 86% are pro-shari’a, of whom 62% favor the death penalty for apostasy. Total: 0.6%.
Afghanistan has about 1.8% of the world’s Muslims, of whom 99% are pro-shari’a, of whom 79% favor the death penalty for apostasy. Total: 1.4%.
Pakistan has about 11% of the world’s Muslims, of whom 84% are pro-shari’a, of whom 76% favor the death penalty for apostasy. Total: 7.0%.
Egypt has about 5% of the world’s Muslims, of whom 74% are pro-shari’a, of whom 86% favor the death penalty for apostasy. Total: 3.2%.
Jordan has about 0.4% of the world’s Muslims, of whom 71% are pro-shari’a, of whom 82% favor the death penalty for apostasy. Total: 0.02%.
Palestine has about 0.3% of the world’s Muslims, of whom 89% are pro-shari’a, of whom 66% favor the death penalty for apostasy. Total: 0.02%.
So all these pro-death-penalty-supermajority countries […] actually turn out to represent less than 13% of all Muslims worldwide (and well over half of those are in Pakistan alone).
While I definitely agree that that number’s still way too high for the proper exercise of religious freedom and civil liberties, surely you must see how silly it makes you look to talk as though it implies that most Muslims support such positions.