Is the commonly accepted Universe age of 13.8B years really accurate? Hmm...challenging the error margin of a specific calculation result of a specific model based on confirmed inconsistencies is regarded as "opinion-based". Interesting. Just curious, is the rationale of closing a "opinion-based" question also "opinion-based"?

According to the calculation of the cosmological standard model $\Lambda CDM$, the age of the Universe is 13.8B years old. This claim is more or less supported by observation of oldest galaxies/stars in the universe.
But is 13.8B really accurate as inferred by $\Lambda CDM$?
Recently there were alarming inconsistencies turning up regarding the Universe's late-time history at low redshift, evidenced by the contradicting numbers of Hubble constant ($H_0$) measured by supernovae/cepheid variable ladders with what is predicted by $\Lambda CDM$ which is calibrated from CMB (Cosmic microwave background) observations and BAO (Baryon acoustic oscillations) constraints. This contradiction is called Hubble tension, or even "Hubble crisis" according to some cosmologists.
If the Hubble tension turns out not to be a systematic measurement error, it could have real implications on the accuracy of dark energy density ($\Omega_\Lambda$) and the true age of the Universe. The standard cosmology model $\Lambda CDM$ has been known as the "concordance model". Given the "Hubble tension" and other inconsistencies (e.g. the controversy surrounding $\sigma_8$), are we sure  $\Lambda CDM$ is a "concordance model"?
Shall we take $\Lambda CDM$'s calculation of the Universe being 13.8B years young with a grain of salt? Should we put a much higher error margin on the claimed age number? In other words, I am questioning that when the Hubble tension is eventually resolved, a new value for the age might exceed the bounds of the commonly agreed +/- uncrtainty error that accompanies the 13.8B value.

Added note: see a related question here.
 A: The significance of the tension is not that the age measurement is off by much, but rather such a tension strongly suggests that we have not yet correctly understood all the relevant physics. So the most likely outcome is that the physics gets understood better and all the age measurements turn out to be roughly right, just not quite as accurate as has been estimated on the basis of the models used so far.
I am not working directly in this area, so I cannot give an estimate of what the range of uncertainty might be. But it is clear from the publications that the Planck collaboration published measured values of cosmological parameters based on assumptions which included, among others: that if there is any spatial curvature, it is negligible; that if there is any local flow or other such inhomogeneities in the cosmic fluid, then its effects are negligible; that the dark energy has the form of a cosmological constant; various things to do with neutrinos and lensing which I don't claim to know much about. As soon as one allows that things like this cannot necessarily be assumed, one will get bigger error margins. So it seems to me that the error margins published by them are indeed a bit misleading, but I am not able to assess what would be a fairer statement. I note that Di Valentino, Melchiorri and Silk (2015) published a comparison of a 6-parameter model and a 12-parameter model. The error margin in the baryon density parameter in the 12-parameter model is twice what it is in the 6-parameter model. The error margin in the cosmological constant in the 12-parameter model is about 4 times larger than in the 6-parameter model.
The error margin in the Hubble parameter in the 12-parameter model is $4.8$ times larger than in the 6-parameter model. Yes that's $4.8$ times.
So this indicates the kind of thing that can happen. More work has been done since then, of course.
A: With $H = 73 km/s/Mpc$, the age of the universe is about 13.4 billion years, a number still comfortably above the age of the oldest globular clusters.
Caveat: this estimate was obtained by taking the inverse of the Hubble constant, which is a cruder way of estimating the age of the universe since it doesn't take into account the density of matter, radiation & dark energy. It is still a reasonable estimate however, and illustrates how much changing the Hubble constant might change the age estimate.
