EL >= 8 uses chrony and not ntp.

defaults/main.yml

@@ -1,5 +1,6 @@
 ---
-ntp_service_enabled: True
+ntp_service_install: True
+ntp_service_enabled: '{{ ntp_service_install }}'
 ntp_statistics_enabled: False
 
 ntp_allow_external_clients: False

tasks/main.yml

@@ -15,11 +15,13 @@
     service: name=ntp state=stopped enabled=no
     when: not ntp_service_enabled | bool
 
-  when: ansible_distribution_file_variety == "Debian"
+  when:
+    - ansible_distribution_file_variety == "Debian"
+    - ntp_service_install
   tags: [ 'packages', 'ntp' ]
 
 - block:
-  - name: Install the ntpd server
+  - name: Install the ntpd server on CentOS <= 7
     yum: pkg=ntp state=present
 
   - name: Install the ntp configuration.
@@ -39,5 +41,20 @@
     when: firewalld_enabled | bool
     tags: [ 'packages', 'ntp', 'firewall', 'iptables_rules' ]
 
-  when: ansible_distribution_file_variety == "RedHat"
+  when:
+    - ansible_distribution_file_variety == "RedHat"
+    - ansible_distribution_major_version <= 7
+    - ntp_service_install
+  tags: [ 'packages', 'ntp' ]
+
+- block:
+  - name: Install the ntpd server on CentOS >= 8
+    ansible.builtin.dnf:
+      pkg: chrony
+      state: present
+
+  when:
+    - ansible_distribution_file_variety == "RedHat"
+    - ansible_distribution_major_version >= 8
+    - ntp_service_install
   tags: [ 'packages', 'ntp' ]