Dating in academia
These techniques are applied to igneous rocks, and are normally seen as giving the time since solidification.The isotope concentrations can be measured very accurately, but isotope concentrations are not dates.
For example, potassium-40 decays to argon-40; uranium-238 decays to lead-206 via other elements like radium; uranium-235 decays to lead-207; rubidium-87 decays to strontium-87; etc.
Overall, the energy of the Earth's magnetic field has been decreasing, so more C is being produced now than in the past.
This will make old things look older than they really are.
Clearly, such huge time periods cannot be fitted into the Bible without compromising what the Bible says about the goodness of God and the origin of sin, death and suffering—the reason Jesus came into the world (See Six Days? He said, This only makes sense with a time-line beginning with the creation week thousands of years ago.
It makes no sense at all if man appeared at the end of billions of years.