A 747 has a 15:1 glide ratio, so if they’d just run the fuel tanks dry at 45000 feet and glide the rest of the way in, they could get another 110 nautical miles of range out of it - a 1.5% improvement. If they left off the landing gear and just pulled a Sully in the nearest river every flight, that’d save thousands of pounds of weight increasing the range even more - the tires alone weigh over two tons.
Lamenting a loss of throw weight when you’re able to reuse the launch vehicle is like lamenting the loss of range imposed on your 747 from having to carry tens of thousands of pounds of landing gear.
The ROCKET has a 0:1 glide ratio.
It must sustain thrust all the way back to the landing pad.
Additionally, there is significant structural mass added to the vehicle to be able to land.
Refurb and Recycle costs are also significant, as we learned with Shuttle.
It would have been cheaper to throw the SRBs away than the total costs of making them reusable.
It was a political design, not an engineering, cost/benefit design, because the concept of recycling was sexy.