There are differences in certain situations.

If you file separately there are a few credits you cannot claim like the earned income tax credit, child and dependent care credit, and some education related credits. So if you would get those credits filing jointly is generally better than separately.

Also to claim medical expenses you need them to be more than 7.5% of agi. If one person has a bunch of medical expenses it might be more than 7.5% of their agi but not of the joint AGI. In that situation jointly might be better.

There are a ton of edge cases where one or the other is better. In most cases it should be the same or very close to the same, but sometimes there are large differences.