In football, loyalty doesn't do anything now, if club can't be loyal to you, then you don't have to be loyal to club. Play and shine, play for the little moment you have to play and if you are lucky to play 90 minutes, then play but when club that are ready to pay you higher amount or give you more years to play, sign for them, leave the club, if you didn't leave they would definitely leave you at the end of the day. Loyalty won't pay you pension after you retire and it's not all players that are lucky to play more than 30 years, most English club won't appreciate you if you clock, close or above 30 years of age.
Upon how much Antonio Rudiger played for Chelsea, because he is close 30 years of age, they didn't give the contract he want to him and he is a player that deserve the best. He even demanded 2 years contract but because he would clock 30 next season, they denied him the contract but Real Madrid value him and they gave him higher of what Chelsea fail to give him with 4 years contract, his contract would lapse by the time he's 33 years of age, isn't that wonderful? Even if he can't play till 33 years of age, I'm sure he would work for his money, he's a good player that works for what he earn.
If club show loyalty by increasing your salary, even when your contract never finish, then you should also show loyalty by playing for then with all your strength. Last season, Chelsea increased Mason Mount's salary and they have been talking on how they would add more to his money in the coming season again as Thomas Tuchel said he want to build the team around Mason Mount.... That is an example of Loyalty from the club, why won't he play with his last breathe for them? Despite the fact that he lost penalty against Liverpool on Carabao Cup final, they are still talking about how to increase his salary.