S2せるのLv.14内にポケストップの数が規定数以上できると、その中のうちの一つがジムに昇格しますが、どのポケストップがその対象となるのでしょうか？
写真の枚数といいねの数の合計が多いものがジムになるという噂を見聞きしたことがあります。そこで、同じ人が何枚も写真あげたりいいねしてもカウントされるのか、同じ人が複数枚写真をあげたり、いいねするのはカウントされないのかどちらでしょうか？ もし後者なら、やりたい放題じゃないですか？
後者は追加する枚数や写真の質（別の角度、昼や夕方、夜などの時間帯の違い）などにもよりますが、不必要に同じ人が複数の画像を送信するとスパム行為の違反として処分対象になります。絶対にやってはいけません。
推測ですが一人で写真をいくつ追加してもサムズアップを複数の写真に入れても影響はないでしょう。
It is almost certain that this used to be the case but is no longer true.
Photo likes are a feature in Ingress which is part of the gameplay. This was used by Niantic to pick which pokestops to turn into gyms, which frustrated a large portion of the Ingress community because Pokemon Go players were affecting how Ingress portals were being used.
It also allowed the community to effectively pick gyms, but this doesn’t mean everyone was happy with those choices.
More recently, this feature has stopped being used and the gym is selected at random (or as close to random as can be perceived) from the available wayspots.
Photo likes are now solely for choosing the cover photo.
The community has observed that Pokestops that are used as Showcase stops will not be promoted to gyms, even if not actively hosting a Showcase.