R136a1 is a very massive star, but has a comparatively small diameter.
According to
Wikipedia 315 solar masses and
28.8 - 35.4 solar diameters. (About 0.3 au)
This seems to be the rule in real life. Stars with very high mass, but comparatively low diameter, and stars with lesser mass, but very large diameter.
For example
UY Scuti with
7-10 solar masses and
1708 ± 192 solar diameters. According to
Wikipedia.
(Other sources say 20 - 40 solar masses
I apparently read some garbage science journalism, then.
Finding an anomalously large star just means you got lucky. They're also easy to spot on account of their size. Find a bunch of these and you may have a point relating to the statistical distributions.
I found an even bigger star, 0-0-0-134-21922-0-0-27, not too far away by eyeball. You're right that bigger stars are easier to spot, but that's also true in real life and I'm doing a million times better than the entire astronomical community. Also, there's the size issue. UY Scuti is the largest star
ever discovered. I'm finding stars twice as big whenever I glance around.
EDIT: Actually, now that I compare it to the Milky Way, it seems that I can't spot any stars at that distance. They don't even show up. Seems like that was just a galaxy of incredibly massive stars. Is that scientifically accurate? Age could explain size but not mass.
RMC136a1=315+60/−50 M☉
Okay dude, what?