Why do you keep asking everyone else when you're unwilling to answer for yourself? My baseline for truth is rooted in god and the cosmic Christ, but is a boots-on-the-ground best guess glimpse at best. I'm just one human following in a long line of humans going through new iterations and updates over millenia trying to inch closer and closer to that which is unknowable. I see truth as a beautiful gem, that is real, but every time you turn it and look at it a different way it reveals things that are new and different, it obstructs things you saw before, and is forever re-shaping our vision in unexpected ways.
Yes, I perceive truth has changed. Because it has. But even if it hasn't, I am nothing more than my perception, and we are nothing more than our perception, so the functional difference between the truth and our perception of the truth is non-existent. You can wax poetic about how The Truth Is Out There, but if there are things that the absolute best of our kind held true for thousands of years that ended up not being true, well, it doesn't really do a lot of practical good clutching to that pearl so tightly does it? Other than give you and I some fleeting comfort.