I disagree. It's a sign of progress. The fact such a ship can exist really conveys the sense that the status-quo has changed, and I love that - too many franchises are scared to change the status-quo. The ship opens up writing possibilities, and not just because they now have comparable firepower to larger threats.
The thing is that the UNSC /shouldn't/ be like that, not four years after a war that lasted a quarter of a century and saw, until the retcon, every single world humanity had colonized lost, and the homeworld under a near-hopeless siege, and only 'won' thanks to what amounted to a mulligan. The UNSC /barely/ survived. It shouldn't have 'become the giant' in a post-war galaxy, had new fleets of advanced warships or a military that was capable of standing up and staring down the Elites or any other Covenant faction.
Or even thought about allowing any Covenant species at all to settle on Earth.
The Infinity is the mark of bad writing, made largely for real world reasons in the hopes of wowing and stunning audiences in the hopes that said audiences would just sign on with the new owners of the Halo franchise. There was so much more that could have been done with depicting humanity as not the victors, but just survivors trying to rebuild what was lost.