Air carrier pilot reported they were instructed to hold short of a runway but the taxiway was not long enough for their aircraft to remain clear of the runway. The reporter stated the departing aircraft was within feet of their aircraft. The reporter also observed an aircraft taking off with an additional aircraft holding on an adjacent taxiway but not clear of the runway.

Narrative

While in a line up for departure on XXL (approx number 4) the active takeoff runway was changed to XYR. Instruction was given to about 10 aircraft to follow each other to XYR. We were taxied down XXL; left on XZL to exit at Taxiway 1 and left on Taxiway 2. While taxiing down XZL in poor visibility conditions Aircraft Z was given clearance to line up and wait on XYR. The controller seemed overworked. We exited the runway on Taxiway 1. When approaching number 2 in the line up on Taxiway 2 for XYR we asked the tower to get out of the line up for operational reasons (fuel below min take off fuel and flight planned into severe). Aircraft Y behind us requested the same. The instructions to us were 'taxi on to XYR; exit at Taxiway 3 and hold short of Taxiway 2; make sure your tail is clear of XYR'. Holding short of Taxiway 2 we were not certain that it was possible to have adequate clearance of aircraft taxiing on Taxiway 2 and being clear of XYR. Aircraft Y went by; the wing of the aircraft was within feet of our cockpit window. Aircraft Z was about to be next. We informed the tower that we felt unsafe. Aircraft Z was told to stop. At the same time Aircraft Y was given 'taxi on to XYR; exit at Taxiway 4 and hold short of Taxiway 2. Aircraft Y extended from the XAR exit to the tail of the aircraft on to runway XYR. We immediately informed the tower. In an abrupt tone we were told not to intervene and that it did not matter what we saw. We were told that it goes by what the controller sees on the radar. Aircraft Z was cleared for take off on XYR while Aircraft Y had not fully cleared the runway. Cause: Controller overload; carelessness and disregard for pilot safety concerns. No aircraft should be cleared to line up and wait in poor visibility while aircraft are taxiing down the runway in the opposite direction. Suggestion: No aircraft should be cleared for take off while a significant portion of another aircraft is on the runway. No pilot advising the tower of an unsafe situation should be dismissed.