That some theories are proven false does not negate the fact that other theories are proven true.
The “cosmic background radiation” remains. Our interpretation of it may not perfectly line up with other age-of-the-universe theories, but it certainly does not come anywhere close to lining up with the “young Earth” theory.
It is sensible to expect: however the universe came into being, there must be a sane scientific explanation of the process. As an engineer, I assure you that my creations are the result of systematic processes adhering to basic rules, where a starting state was crafted and subsequent behavior can be directly traced to that beginning - it did not “hit the ground running” in whatever state you observe it in. Likewise, it is reasonable to expect God created the universe in some starting state, which we can understand best by tracing current states back to that point based on basic principles - and not by assuming it “hit the ground running” in an in-progress form ... to assume so makes the absurd question viable: “so what makes you think God didn’t just create the universe about 20 minutes ago?”
It's not necessarily so "sensible" to believe the universe "came into being" in that the majority of atheistic scientists have reverted to Hoyle's old "steady state" theory that the universe is eternal and has always been. The are forced to take this position because any scenario where the universe "begins" would require a God. They can't get around the singularity even under a "multi-verse" construct. To argue otherwise is to discared the elementary logical laws of identity, contradiction and cause and effect. Of course if you are relying on the "steady state" model in an empirical enviorment then you are just using an infinite regression to avoid the conflict and the issue.
Yes, but it may be the 'hum' of an operating Universe (ergo a constant) and may not have anything to do with the age of the Universe.
It is sensible to expect: however the universe came into being, ...
Why can't the universe be 'infinite and eternal' ?
We have no idea what the Universe even is, yet we think we know it's size, shape, and date of birth (and we are completely wrong about all three).
We claim we have the birth certificate of the Universe, but with all our technology, we can't find the birth certificate of the current President of the US.