Doubtlessly true.
As Stellar Evolution progresses on the Main Sequence of the Hertzsprung-Russell Diagram, the fuel in the core is used up. Then the core becomes denser and the next layers compress and fusion moves outward. The net effect is that stars grow gradually hotter as long as they are on the Main Sequence. The Sun now radiates 30% to 50% more energy than it did when life began.
David F Mayer