How old are you?
What type of athlete were you in High School or College?
I’ve worked with many riders over the years who were much stronger than me per their FTP and age (younger by 20 yrs), but they just did not know how to sprint.
The podcast has some great videos/discussion on sprinting. Once you realize that the most likely issue is technique and not leg strength, you can focus on that.
Is your 1050 watt sprint outdoors or on the trainer?
Most sprint power comes through the upper body and core. Sometimes my hands would ache after a really hard sprint from gripping the bars. Just an indication of how involved the upper body is. The upper body is static but you should be trying to rip the bars off in the first 10 pedal strokes.