What do you mean by gold? Lowest, mid or highest tier? If lowest, you won't see that much recognition. There are so many people out there with the lowest tier.

Regarding upgrades, your chances are pretty slim and unforeseable.
On domestic flights you're probably always going to be overtaken by the highest tiers receiving complimentary upgrades. And if you're not, anyone who purchased a higher fare class is going to be upgraded if the flight is overbooked.
On international flights, it depends on which airline you fly and how they handle overbooking-situations.

I got status with BA and was upgraded on LHR-JFK once from Eco to Eco+ and from JFK-LHR twice. When did I get it? Once at BP check at T5(LHR) and twice at the gate in New York. Always was a nice surprise, but still, it's just Premium Economy.
I can't exactly speak for AA or other airline's policies, but on international travel you'll probably never see complimentary upgrades. As for IRROPs or overbooking situations, they'll most likely go down three lists: 1st depending on fare class purchased, 2nd their own tiers, 3rd alliance tiers where 2 and 3 could be intertwined. E.g. AA will certainly upgrade their highest tier before BA's highest tier, but might upgrade BA's highest before their second-highest. But that's certainly nothing you can count on.

They might also upgrade you to give you "a shot" of the higher cabin, maybe you'll spend more?
US based systems however give you at least some kind of domestic complimentary upgrades. Then it just depends on the status-load of the flights as well as the cabins (size/number of seats).