Realistically, Energy never had a wait.
So if you’re only getting 1000 guests through the doors, Guardians is not only serving more guests per hour (which effectively is what you want with capacity) but also pulling them from the rest of the park for a consistently long amount of time (something Energy excelled in).
Even with virtual queue, the multiple pre-shows, queue, and ride experience are at least a 30 minute experience (even when the queue is absolutely minimal).
So if you can give 2000 guests the experience in an hour, you’re effectively removing 1000 guests per hour from the park.
Even if we’re generous to Universe of Energy and call it an hour-long experience, that’s still an only 1000 guests fully pulled from the park for the hour assuming the extremely underutilized capacity it always had.
Guardians pulls no one who does not care for rollercoasters, or anyone under 42 inches, or that do not like rollercoasters or rotating thrill rides. It actually causes more people to wait around and take up capacity in other attractions, dining and venues near and far of the park.
Near the end no one cared about Ellen's Energy Adventure. But the ride system as a whole was over 40 year old and based on properties without the connection even the refurb in the mid 90s had.
But all this moot at the attraction also did not do what Disney wanted, which was replace something and gain more attendance out of it to match the ROI.