diff --git a/stan/math/prim/meta/is_kernel_expression.hpp b/stan/math/prim/meta/is_kernel_expression.hpp
index 0dc2e96332e..780936b72ea 100644
--- a/stan/math/prim/meta/is_kernel_expression.hpp
+++ b/stan/math/prim/meta/is_kernel_expression.hpp
@@ -184,6 +184,7 @@ using require_any_not_prim_or_rev_kernel_expression_t = require_any_not_t<
 
 // STAN_ADD_REQUIRE_UNARY(nonscalar_prim_or_rev_kernel_expression,
 //    is_nonscalar_prim_or_rev_kernel_expression, opencl_kernel_generator);
+template <typename T>
 using require_nonscalar_prim_or_rev_kernel_expression_t
     = require_t<is_nonscalar_prim_or_rev_kernel_expression<std::decay_t<T>>>;
 
diff --git a/stan/math/prim/meta/require_generics.hpp b/stan/math/prim/meta/require_generics.hpp
index 06ae2715cdf..d8343d0bbaa 100644
--- a/stan/math/prim/meta/require_generics.hpp
+++ b/stan/math/prim/meta/require_generics.hpp
@@ -63,11 +63,11 @@ using require_any_not_st_same
 
 template <typename T, typename S>
 using require_vt_same = require_t<
-    checker<value_type_t<std::decay_t<T>>, value_type_t<std::decay_t<S>>>>;
+  std::is_same<value_type_t<std::decay_t<T>>, value_type_t<std::decay_t<S>>>>;
 
 template <typename T, typename S>
 using require_not_vt_same = require_not_t<
-    checker<value_type_t<std::decay_t<T>>, value_type_t<std::decay_t<S>>>>;
+    std::is_same<value_type_t<std::decay_t<T>>, value_type_t<std::decay_t<S>>>>;
 
 template <typename T, typename... Types>
 using require_all_vt_same
@@ -145,11 +145,11 @@ using require_any_not_st_convertible = require_any_not_t<std::is_convertible<
 
 template <typename T, typename S>
 using require_vt_convertible = require_t<
-    checker<value_type_t<std::decay_t<T>>, value_type_t<std::decay_t<S>>>>;
+    std::is_convertible<value_type_t<std::decay_t<T>>, value_type_t<std::decay_t<S>>>>;
 
 template <typename T, typename S>
 using require_not_vt_convertible = require_not_t<
-    checker<value_type_t<std::decay_t<T>>, value_type_t<std::decay_t<S>>>>;
+    std::is_convertible<value_type_t<std::decay_t<T>>, value_type_t<std::decay_t<S>>>>;
 
 template <typename T, typename... Types>
 using require_all_vt_convertible
@@ -225,11 +225,11 @@ using require_any_not_st_assignable = require_any_not_t<std::is_assignable<
 
 template <typename T, typename S>
 using require_vt_assignable = require_t<
-    checker<value_type_t<std::decay_t<T>>, value_type_t<std::decay_t<S>>>>;
+    std::is_assignable<value_type_t<std::decay_t<T>>, value_type_t<std::decay_t<S>>>>;
 
 template <typename T, typename S>
 using require_not_vt_assignable = require_not_t<
-    checker<value_type_t<std::decay_t<T>>, value_type_t<std::decay_t<S>>>>;
+    std::is_assignable<value_type_t<std::decay_t<T>>, value_type_t<std::decay_t<S>>>>;
 
 template <typename T, typename... Types>
 using require_all_vt_assignable
@@ -306,11 +306,11 @@ using require_any_not_st_constructible
 
 template <typename T, typename S>
 using require_vt_constructible = require_t<
-    checker<value_type_t<std::decay_t<T>>, value_type_t<std::decay_t<S>>>>;
+    std::is_constructible<value_type_t<std::decay_t<T>>, value_type_t<std::decay_t<S>>>>;
 
 template <typename T, typename S>
 using require_not_vt_constructible = require_not_t<
-    checker<value_type_t<std::decay_t<T>>, value_type_t<std::decay_t<S>>>>;
+    std::is_constructible<value_type_t<std::decay_t<T>>, value_type_t<std::decay_t<S>>>>;
 
 template <typename T, typename... Types>
 using require_all_vt_constructible = require_all_t<std::is_constructible<