perf: disable accessibility for layout views (#10482)

a11y is enabled by default on controls still, this just disables on layouts alone as unnecessary.
It can be enabled on a per layout view basis if needed anytime.

packages/core/accessibility/accessibility-properties.ts

@@ -26,6 +26,7 @@ function makePropertyEnumConverter<T>(enumValues) {
 
 export const accessibilityEnabledProperty = new CssProperty<Style, boolean>({
 	name: 'accessible',
+	defaultValue: true,
 	cssName: 'a11y-enabled',
 	valueConverter: booleanConverter,
 });