Those intervals are great for simulating race demands in something like a crit, or even a zwift rate, where you have lots of speed fluctuations, and moments where it's balls out, and then lulls, but agreed, those will not help your top end sprinting...
The only way you can truly simulate emptying the tank on a proper sprint, is by doing sprints, with lots of rest... Sprinting workouts tend to be incredibly easy for 90% of the workout, and incredibly hard for the remainder... You can get more fitness value from the workouts with adding in progressive wind-ups (which reduces the pure rest a bit, and also simulates the dynamics of a road race leading into the sprint)... On the road, the best ways to work on this is big gear sprinting uphill, or motorpacing... My favorite road sprint workout was with a group of 8-10 people and a moto, on a 1mile loop we'd do progressive laps at 40km/h. 45, 50, 55, 60, 65, and then take a break (you'd also be rotating through the paceline, realizing you're working hardest at the back, and getting the best draft right behind the moto... also great for cornering skills, because if you touch the breaks at some of those speeds, you get yourself and everyone on your wheel dropped, and probably a waterbottle thrown at you...), we'd usually do two to three sets like that... Then we would do a series of wind up sprints, where we'd do a couple of laps progressively building speed, and with 400m to go at the end of the second lap, the moto would have the speed lifted to around 70km/h and then pull off to the side and then it would be a bunch sprint, followed by a 5-6min super easy, and then repeating... we'd build our way up to 5 or 6 of those sprints...
You can simulate those types of workouts on the trainer, but should never be doing the top end sprinting in ERG mode... If you design your own workouts on something like Zwift, you need to make sure you're free riding for those top end efforts, because the resistance lag pooches the intervals otherwise...
The only way you can truly simulate emptying the tank on a proper sprint, is by doing sprints, with lots of rest... Sprinting workouts tend to be incredibly easy for 90% of the workout, and incredibly hard for the remainder... You can get more fitness value from the workouts with adding in progressive wind-ups (which reduces the pure rest a bit, and also simulates the dynamics of a road race leading into the sprint)... On the road, the best ways to work on this is big gear sprinting uphill, or motorpacing... My favorite road sprint workout was with a group of 8-10 people and a moto, on a 1mile loop we'd do progressive laps at 40km/h. 45, 50, 55, 60, 65, and then take a break (you'd also be rotating through the paceline, realizing you're working hardest at the back, and getting the best draft right behind the moto... also great for cornering skills, because if you touch the breaks at some of those speeds, you get yourself and everyone on your wheel dropped, and probably a waterbottle thrown at you...), we'd usually do two to three sets like that... Then we would do a series of wind up sprints, where we'd do a couple of laps progressively building speed, and with 400m to go at the end of the second lap, the moto would have the speed lifted to around 70km/h and then pull off to the side and then it would be a bunch sprint, followed by a 5-6min super easy, and then repeating... we'd build our way up to 5 or 6 of those sprints...
You can simulate those types of workouts on the trainer, but should never be doing the top end sprinting in ERG mode... If you design your own workouts on something like Zwift, you need to make sure you're free riding for those top end efforts, because the resistance lag pooches the intervals otherwise...