Low water pressure at toilets after main supply valve replacement
Some toilet valves can be taken apart to flush the sediment out. Turn off the valve that supplies the toilet and flush it. This will allow the fill valve to depressurize. I have been able to clean two types. Both had some arrows / instructions, one you pushed down and rotated the top of the fill valve and it pulled straight up then slight turn the water on--this clears the stuff in the line (I found putting a glass on top allowed me to turn the water up and really clear the line).

The second type I have only had ~75% luck with they have 2 plastic clips that you slip a small screwdriver under and lift the cap same as above for flushing, but use caution the plastic breaks very easily and a valve replacement is needed. As for the other valve / tub, if it has a shower head or arrestor they need to be cleaned also. If it has washerless valves you may need to disassemble the valve flush and reassemble.