52% is not a large majority of LNP voters,* The article I linked interviewed a Liberal MP who is part of a parliamentary friendship group for a republic. Republican sentiment exists across the political spectrum. Moreover, I'd wager public sentiment will change once Charles is king too. Which is my point. As I have said previously, I think once the Queen dies, Australia will reevaluate its relationship with the Royal Family and that it is likely we will have another Referendum on the Monarchy.
*Not to mention, that's just one poll. I'm sure we all know after the last 5 or so years (Brexit, Trump) that polls aren't always accurate
52% of LNP voters wanting to keep the monarchy to just 27% of LNP voters wanting a republic is actually a huge 25% majority for keeping the monarchy with LNP voters.
Yes there have always been a few Liberal republicans within the Coalition (remember Malcolm Turnbull led the Republican side to defeat in the 1999 monarchy referendum) but most Liberal voters and the overwhelming majority of National party voters are monarchists. Howard, Abbott and now Morrison have all been monarchists as leaders of the Coalition. It is Labor leaders like Hawke, Keating, Rudd, Gillard and now Albanese who have been republicans.
Note too on that poll more Labor voters, 34%, wanted to keep the monarchy than the 27% of LNP voters who wanted a republic.
William as by then Prince of Wales and Kate are also very popular in Australia so would play a big part in the Australians for a Constitutional Monarchy campaign if there is another referendum after the Queen dies, not just by then King Charles.
You mentioned the 2016 votes for Brexit and Trump, remember it was working class and lower middle class voters especially in suburban and rural areas who won those elections for Leave and Trump. Remember in Australia it is working class and lower middle class voters, especially in rural areas, who tend to be most pro monarchy. It is liberal upper middle class city dwellers who are the most likely to be republicans, just as it was liberal upper middle class city dwellers who were most likely to be for Hillary in the US or for Remain in the UK.
In the 1999 referendum for example the ACT voted 63% for a republic and Victoria, containing Melbourne, voted only 50% for the monarchy and NSW, containing Sydney, voted 53% for the monarchy compared to a 55% vote for the monarchy across Australia. Rural Queensland however voted 63% for the monarchy and Western Australia also voted 58% to keep the monarchy