Nick Greiner, the federal Liberal president, has joined calls for the party to change the rules to make it harder to overthrow a leader, saying the coup culture in Canberra needs to change.

He has criticised Tony Abbott for the role he played in Turnbull’s downfall, saying Abbott spent too much energy in recent years focusing on the Liberal party’s “internal differences” than on fighting the opposition.

He predicted history would judge Malcolm Turnbull more kindly than some of his colleagues, saying the former prime minister had run the best cabinet government since John Howard.

He also agreed with Turnbull that there had been some elements of the media working against him over the past three years.

“You would be deaf, dumb and blind not to think that there was an element, an unusually vitriolic element – there’s always elements of criticism and involvement from [the media] in politics, [but] I think there’s been an extreme version of that in the last three years since Malcolm Turnbull became prime minister,” he said.

“That must have had some part in the events, but I think at the end of the day the parliamentarians, the politicians, have a pretty acute sense of political smell if you like, and they’re the ones who ultimately made the decisions, good or bad.”

Speaking on Sky News on Sunday, Greiner said he had to laugh when he saw the former Labor leader Kevin Rudd giving a homily about how the voting public didn’t like leadership spills, because Rudd was “the father of pulling down sitting prime ministers”.

But he admitted that, like Labor had done, the Liberal party would benefit from changing the rules to make it harder to change leaders.

“I’m not opposed to that idea, I think it’s an obvious directional thing,” he said.

“I don’t think it’s on the top of Mr Morrison’s list, nor should it be, but I think the organisation, not surprisingly, would be happy with some sort of model [change].

“There are already members of the parliamentary party advocating it and Mr Morrison does not have a tin ear, but yes certainly I think it’s something that ought to be on the agenda,” he said.

Greiner’s call for the Liberal party to overhaul its leadership rules comes after John Alexander, a Liberal backbencher, said the party’s leaders ought to serve a full term before seeking a fresh endorsement from their colleagues before an election.

Greiner said he was “not supportive” of the coups because sitting prime ministers deserve a chance to be evaluated by the Australian public.

However, he said the switch to Morrison would provide the party with an opportunity for “genuine unity” because Morrison was the obvious centre candidate, as opposed to Peter Dutton.

He also stopped short of calling for Abbott to leave parliament, saying sitting MPs don’t appreciate getting that type of advice from people who are no longer MPs.

“There are obvious options [for him],” Greiner said.

“I don’t mind what options various individuals in the parliamentary party take, that’s for them, the important thing is the outcome, whether they’re in Timbuktu or Canberra, [that] they have their focus 100% on having the Coalition in the best position to win next year.”

He said history would judge Turnbull more kindly because he ran a “very good government”.

“He certainly ran the best cabinet government since John Howard, and public servants who don’t have a political axe to grind will tell you that.”