Often, yes. A multi-stop ticket priced as one through-fare frequently beats stitching together separate round-trips or one-ways to the same cities. Separate one-ways can win for short-haul hops, but multi-stop pulls ahead once you add long-haul legs and multiple continents.
Often, yes. A multi-stop ticket priced as a single through-fare frequently beats stitching together separate round-trips or one-way flights to the same cities. The savings come from how the routing is constructed, not from a discount code.
Here is the trade-off. Separate one-ways can win when your cities are all cheap, short-haul hops, or when one low-cost carrier covers most of your route. A multi-stop fare pulls ahead as soon as you add long-haul legs, several continents, or any backtracking that would each be priced on its own if you booked piece by piece.
The only way to know for certain is to compare your exact routing. Send your consultant the cities you want and they will price it both ways and tell you which is cheaper, including the fare rules and change flexibility that separate budget tickets usually do not include.