Unlike all of the former Dem Presidents it has long been the policy of the former " R " Presidents to NEVER comment on policy or the performance of the current President .
You can trace this practice as far back as President Eisenhower .
However every single Dem Ex President since JFK has been an active commentator on the performance of the Incumbent President regardless of the Party of the Incumbent .
Further every single former "R" President has taken the approach that they should stay out of Political issues and rarely if ever have backed any candidate for any office .
[ Just like Baseball --- you can look it up ]