No my dear! Just because some thing is used in some cases it does not mean it is to be used always for carrier ships!
First modern Bulbous bows have been incorporated in designs since 60s. There are MANY MANY MANY consideration to bulbous bows. Things like, if your ship is going to operate on same speed during most of it life? Size of your ship? Even schedule of your operation.
Bulbous Bows work by destructive interference of wave generated by ship's hull and the bulb. Remember, waves generated by bulb and hull MUST coincide or bulb will WORK AGAINST you if a constructive interfence happens. It will pitch your ship EVEN WORSE. Now if you have taken physics in high school, you know what decides the interfernce? its the wave length of the wave. Wavelength of waves in water (caused due to moving objects like ships) depend upon the velocity of ship/object. If you can guarentee that it will always move at a constant speed, then the bulb makes a LOT OF sense. if not, it will HURT the ship (fuel and pitching) and not help because it can cause constructive interfence of waves.
Sure as hell Indian navy knows how it will operate its aircraft carriers and at what speed (constant or changing) or schedule or condition of seas in which it will operate. So thats how these design decisions are made.
US operates its warships and especially carriers over VERY long distances so they have a massive cruise phase where they are moving at a constant speed. (say deployment from East coast to Guam). Here Bulbous Bow will SAVE fuel to navy because ship will be moving at a constant speed.
Indian ships operate in its own pond (Bay of begal, Arabian sea and possibly parts of Indian ocean) so not much of long cruises but short journey to possibly enforce a blockade. So bulbous bow design makes no sense because it is hard to get right and is harmful if Navy wants to use different speeds. So them most likely omitted it.
Source :
Trials are not real use. INS Vikramaditya was commissioned as a combat ship in 2014. Liaoning only entered naval fleets in 2018.