Okay...here's the deal. You can strip the clearcoat and just leave the trailer to oxidize. However, it will most likely not do so evenly. Where the clearcoat has already failed, the aluminum has already begun to oxidize and where it hasn't failed it's still protected. So when you strip the remaining clearcoat, the newly exposed aluminum will have some catching up to do.
Prior to our polishing, our clearcoat had begun to fail over the years and the result was a very
splotchy appearance - see my photo gallery. Yours most likely wouldn't be as bad as the delta between the beginning of clearcaot failure and the removal of the remaining clearcoat isn't as great as on our vintage, but it wouldn't be 'even' either. Eventually, the oxidation would even out more and your trailer will turn a dull grey. The climate and storage conditions where you keep your trailer will determine how quickly the oxidation progresses. Also if one side is exposed more to weather than another, it could effect the splotchiness...more exposure = more oxidation.
Actually, the aluminum skins on the newer trailers (like your '98) have a milled finish that doesn't polish up to a mirror shine anyways without removing the milled texture itself, which would be a tremendous amount of work. Then after that, you would be faced with the chore of maintaining the shine...or expense of a new application of clearcoat.
The final decision, of course, is only one you can make.