First of all, not all all-star appearances are equal. Nunez has been a sparingly used bench player before this year (seriously, 204 PA last year, and only one 15 day DL stint, I think). He's had a good half season this year, but his value is still pretty low. He's 29 years old. If Arcia makes an all-star team in 2018, he will only be 27 years old. Presumably he will play more than Nunez in the meantime too. Given his position, he will probably need to have a better than 118 OPS+ to make an all star team too. If Arcia follows the Nunez path, spends most of his time on Tampa's bench, then makes an all star team in 2018 as a token team representative with a 118 OPS+ and bad defense, I don't think it will be used as much evidence of anything.