Then there's always this hashy version:

my %defaults = (GetAll => 1, Make => 1, MakeOnly => 1);
for (@tabs) {
  $_->{Suppress} = $defaults{$_->{Action}} if exists $defaults{$_->{Ac
+tion}};
}
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which behaves the same as any of your examples, although I don't generally consider "default" to mean "value that clobbers any preexisting value"... You might instead want to include all allowed Actions in %defaults and then, when Action is set, do a

$_->{Suppress} = $defaults{NewAction} if $->{Suppress} == $defaults{Ol
+dAction}
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