There isn't anything wrong with plugging a tire if done correctly. The liberal use of rubber cement is a must. Back in the day, this is how ALL tubeless tires were repaired, I did hundreds (maybe a thousand) of them when I worked at a service station as a teen. I have done many dozens of them since (many of them with the tire mounted on the vehicle, but sometimes it is just easier to remove the tire) and never had a tire failure from doing it.
As far as the tire manufacturer's (and store's) recommendations are concerned, keep in mind that they have a vested interest in selling you a new tire.
Is a plug/patch a better repair? Of course it is, but a patch by itself is NOT. Done correctly, plugging a tire is not as dangerous as some would have you believe.