Exactly. They've brought up nuclear because they're desperate to have some kind of energy policy, but one they know they'll never have to bring to fruition because that allows them to continue with coal and gas for as long as possible.
The LNP doesn't have a legitimate interest in transitioning to nuclear power or they would've begun over the last decade or so that they were in power.
Instead they've proposed - now that they're in opposition - a technology which is banned at the Federal level and individually at the state level, because they know that gives them years of lead time before they ever have to begin the project.
On top of that, all of the proposed sites are owned by companies who've already begun transitioning to renewable generation or renewable storage, and most of them are in states in which the state Premiers have publicly stated that they will not consider overturning their bans on nuclear power.
This is somewhat analogous to the way midterm elections are treated in the US, and a decent comparison would be when Mitch McConnell blocked Obama from appointing a Supreme Court Justice towards the end of his second term.
The Democrats lost seats in Congress during that midterm season, which the Republicans used to claim that the American people had no faith in the Democrats and therefore no faith in Obama. They then used this claim as an excuse to block the Democrats ability to govern.
In this case, the people of France have voted for another party to represent their interests internationally to the EU parliament.
Macron will now face claims within the French government that the people voting against them in the EU elections indicates that they have no faith in his party's leadership and that will make it difficult for him to govern.
With this move, calling an election early, they will have a clear indication of who the French people wish to lead them internally and, if they reelect Macron's party, can dismiss the claims from opposition parties that the people don't trust them.
It's worth mentioning that many governments around the world don't have fixed election cycles the way you do in the US. Instead many countries have an end date by which the election must occur, but a new election can be called at any time before that date if the government thinks it's necessary. A similar thing is currently happening in the UK where the Conservative Party has called an election for early July, even though the election didn't have to take place until late January 2025.