There's also the other side of the coin: living 20 years in a day may be hard on the body, even if you don't have time to actually grow a Rip van Winkle beard. The brain does still have to go through the biochemical acrobatics of experiencing two decades' worth of thoughts. Perhaps Chief O'Brien would indeed have died peacefully in his bed at 140, surrounded by loved ones, but will now have to settle for dying at 120?
If the tech were such that it would shorten your real life, either 1:1 as you imply or at least some "significant" ratio between real life:fake life, then sure this tech would be used sparingly. It is possible the Argrathi tech does this though this is not stated and it is just as possible that it has no effect on the lifespan of the subject compared to if the subject did not experience those decades of fake life.
For sure, we know that the Kataan tech through which Picard experienced his "lifetime" did not shorten his life, at least not on a 1:1 ratio. He lived an entire lifetime on Kataan in 25 minutes. Obviously if the Kataan tech shortened Picard's REAL life on a 1:1 basis, he would have "awakened" dead.