CRJ-900 Captain reported a critical ground conflict when another airline; taxiing at a high speed; came within 50 feet. After inquiring with ATC; the Captain was told by ground control they did not realize the other aircraft was taxiing so fast. Later; during the same taxi; the Captain stated evasive action was needed to avoid a tug that cut in front of the tug.

Narrative

After pushing from Gate XX to XY (tail south) on ramp; called ready on metering. ZZZ Ground cleared us XXR via taxiways. After energizing my taxi lights I visually verified clear left and started rolling forward. As I began to turn left across taxiway another airline suddenly appeared from behind my field of view; taxiing North at 30++ kts. I immediately applied the brakes and avoided taxiing into the path of their right wing by ~50 ft. The other airline never slowed. I immediately queried Ground about the conflict and was told 'sorry; didn't realize how fast he was taxiing.' I was then re-cleared to XXR via same taxiways. Upon looking forward there were two aircraft taxiing south; and I queried Ground again about the taxi conflict and was again apologized to and told my sequence should be the second aircraft. After joining that sequence uneventfully; we were cleared to continue and hold short of XXR. As we taxied south on a taxiway a motorized baggage hauler (no cart on back) was speeding down the access road parallel to the taxiways. Instead of stopping; the baggage hauler continued into my path. I braked so that I would at least be stationary when hit; and the cart swerved off the path and around the front of my aircraft and continued on. As Ground switched us to Tower I informed Tower of the baggage cart and was told 'Unless you have a number there's not much we can do.' In my professional opinion; ZZZ Ground operations would benefit from a 24-hour safety stand-down before someone gets hurt or killed. And the airline X should re-think the operational safety of using the taxiway facing north (away from oncoming traffic) as a startup spot if Ground isn't going to pay any attention to taxi clearances and assign/enforce sequences.ZZZ Ground was clearly not paying attention to sequencing of taxiing aircraft and seemed to expect aircraft to see/avoid and sort themselves out. This is not standard; is very unsafe; and with the taxiway as a north-facing startup spot almost impossible to safely clear northbound traffic as they are not visible from the aircraft until we turn into them. The Ground Controller's subsequent response to both incorrect taxi clearances plus the third response to the rogue baggage tug suggests a culture that is normalizing deviations from safe taxi clearances. ZZZ Ground would benefit from a thorough incident review and safety stand-down reviewing ATC tapes and ground ASDE-X/ADSB tracks. Our competitor should taxi slower and be aware enough to call Ground if an aircraft was cleared directly into their path. And airline X should re-think the safety of the taxiway facing north as a startup spot if ATC can't be trusted. There may not be sufficient space on the ramp to pull forward; and squaring the left turn; without putting the nose of the aircraft into the path of high-speed rogue aircraft going north. This accident was averted because I was moving slowly and looking at exactly the right place to minimize my response time and brake to avoid the collision. Had I been looking anywhere but continuously into the threat the outcome could have been different.