You are naming your font "english". If you call "ebgaramond" it will always take the default ebgaramond features. Just call your font with the name you gave it.

\definefontfamily[english] [rm] [ebgaramond] [features={dlig=no}]
\setupbodyfont[english,10pt]
\starttext
ct st
\stoptext



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Los fines no justifican los medios, porque la medida verdadera de nuestro carácter está dada por los medios que estamos dispuestos a utilizar, no por los fines que proclamamos.
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“You develop an instant global consciousness, a people orientation, an intense dissatisfaction with the state of the world, and a compulsion to do something about it. From out there on the moon, international politics look so petty. You want to grab a politician by the scruff of the neck and drag him a quarter of a million miles out and say, ‘Look at that, you son of a bitch.’” — Apollo 14 astronaut Edgar Mitchell