"You never heard of old Earth creationists? They believe that earth is millions of years old too."
I have indeed heard of them, though I am hard pressed to figure out how this topic came up lol.
Obviously, one side is wrong. I take the side of being an "Old Earth Creationist" myself, given that I believe that the Earth is around 6,000 years old. I am obviously being facetious, since that is not how the debate is normally framed, but 6,000 years is very old to creatures that currently have a life span of only around 70-90 years.
I am convinced by all of the things in evidence that simply cannot exist in a universe that is billions of years old, and many secular scientists indirectly confirm this. For instance, with what we currently know about celestial mechanics, were the galaxies billions of years old, they should have 'spun' themselves into general mush by now vs the well defined spirals we still see. Secular scientists know this, so they dreamed up a substance that no one has ever seen, though they say it is more abundant than the matter we can see- dark matter. It is supposed to be everywhere, but the ONLY place you will find it is in their mathematical equations. They tune their equations based on a priori assumptions, and end up with the answer they want to get.
Then there are recent discoveries, like that of Saturn's rings. Before they crashed the Cassini probe, they learned that Saturn's rings are 'raining' down onto Saturn. At the rate they observed, Saturn's rings should be gone in around 250,000 years. The claim that Saturn and its rings have been around for much longer than that begins to look impossible.
The Hubble Telescope was focused on a section of space that looked to be generally empty, but instead they brought into view billions of galaxies. We are allegedly seeing light that took nearly 14 billion years to get to Earth. This is like looking back in time, a sort of time travel, if you will. If the universe only started 14b years ago, we should not see anything, or only see a lot of chaotic matter that had not yet cooled and coalesced into galaxies. Hmmmmm.
And so on and so forth.