I think the notion of the problem being "too much dopamine" is an oversimplification.
For example, our reward system has a natural regulation mechanism called Coolidge effect, that states that repeated sex with the same partner gets "less interesting", whereas introducing a new partner renews sexual interest with high levels. One of the problems is that porn circumvents this with the endless novelty. You might have noticed, that PMO to the same scene or pic feels less intense than the first time. Same thing.
So you'd have to avoid the Coolidge effect. Meaning, you'd have to have an endless stream of new partners, possibly multiple per day to get even close to the reward center abuse you can do with porn. And then it is still real sex and not artificial like porn.
So: I don't think you can get P.I.ED from real sex, but you sure can become a sex addict.