Beliefs are not facts
Whenever someone says, “I believe …”, then whatever they say next is not true. If it was a fact, there would be no need to declare a belief.
You don’t say, “I believe in squirrels.” You don’t say, “I believe squares have four sides.” It’s just a fact, so there’s no need to take a stance.
You say “I believe” when it’s not a fact that everyone can see. Since people view it differently, you share your perspective on how you see it.
A belief is something you think is true, without proof. A fact is an objective reality — something proven true — verified with conclusive evidence.
No beliefs are true. If a belief was proven true, it would no longer be a belief.
Galileo believed the planets orbit around the sun, but he didn’t have proof. Hundreds of years later, when it was proven true, it ceased to be a belief and became a fact. But in his lifetime, it was just a belief.
Beliefs are a stance on what’s inconclusive. You have to say “I believe …” because it’s not the only answer. It’s not a fact. (Not yet.)
"No beliefs are true. If a belief was proven true, it would no longer be a belief."
I agree with this fundamentally. Truth is procedural, generative. But I feel this contradicts your original definition of truth as "absolute, objective, necessary." What you are saying is a statement (fact, belief) becomes true through verification. But does that mean that until we verified it, the Earth didn't actually revolve around the Sun? This is inconsistent in your book. Truth is both the absolute reality AND the process of squaring a statement with that reality.
In my view, facts have nothing to do with objective reality. Facts are just statements - products of our attempt to communicate with each other.
Nobel Prize winner Bertrand Russell said (from memory) "If you are certain of something, then you are certainly wrong." He meant beliefs of course, not facts. He thought the mark of a true man was the willingness to always entertain a scientific doubt.
I would add—"not the only answer"— that a true person can hold two different hypotheses at once without needing to believe in one to the exclusion of the other. Tolerance of ambiguity is a good source of mental strength.
In my life time I saw light go from waves to particles to wavicles. I saw planets go from orbiting due to gravity to orbiting due to space-time curvature.
And I saw the truth, goodness and beauty of communism crumble with that wall in Berlin. Before that, insurgents would kill for communism; kill anyone trying to cross the Berlin Wall.