How much of an error rate difference are we talking about?

For sure, when you burn a disc, you want a low error rate and no E22 and
E32 errors. However, all other things being equal if we are talking about
BLER of 0.5 versus BLER 3.0, this is not an issue.

I have burned a large variety of discs on different burners and different
speeds for the research I have performed. The TY/cyanine does tend to
produce a BLER <1 on many occasions. The Mitsui/MAM can attain this, but
the BLER is usually slightly higher (in the 2 to 3 range).

That being said, gold metal layer will not corrode, silver alloy will.
Phthalocyanine dye is very stable to light, heat, RH and cyanine is not.
These points are not theoretical.

So, as Jerry briefly pointed out as well, here is a basic example:

Disc A (gold metal/phthalocyanine): Initial Bler = 10.0
Disc B (silver metal/cyanine): Initial Bler =0.2

Disc A is very stable and over 10 years does not change. However, Disc B is
less stable and does change over the 10 years due to exposure to one or all
of the following: light, elevated temperature and relative humidity, high
levels of pollutants from the atmosphere, or exposure from aggressive agent
from poor storage enclosures.

After ten years you have:

Disc A (gold metal/phthalocyanine): Ten year Bler = 10.8
Disc B (silver metal/cyanine): Ten year Bler =100.0

Where would you rather be?