I would suspect the jumper wires. Cheap and crappy Chinese ones are often made with wire that has a very thin metal core and may not even be copper. If their resistance is too high then yes, you will get trouble like that.
I have no problems with breadboard power distribution, but I don't use pre-made jumper wires. Instead I use wire stripped from Ethernet or Telephone cable - 24 AWG SOLID COPPER with colour coded insulation. (Don't use Ethernet patch leaad cable, its stranded and will FUBAR your breadboard.) Each wire is individually cut to length for a neat layout, and when running jumpers between breadboards in a panel to hook up the power bus strips, I put them at both ends of each breadboard. That keeps the resistance as low as possible.
Most signal wires are less critical - if you don't expect more than 10mA through it your jumpers should do, but please check their resistance with a DMM before use to avoid unpleasant surprises (e.g. badly crimped end pins that may barely be making contact).
Here's a VFD clock I built a few months back:
That's the Arduino, four chips, the VFD filament, and a 24V output DC-DC module powering the 12 transistors driving the VFD, all running off the breadboard bus strips distributing 5V from a hacked phone charger (Old phone plug cut off and replaced with switch on left with LED + red and black wires to pins for breadboarding). The 5V rail is within 0.1V of the input voltage everywhere.