Switching from strength to hypertrophy routine make you lose a lot of strength?

[Astronomics]

So I did Starting strength for about 8 months and got to
Squats 260x5
Deadlift 305x5
Military press 120x5
Power clean 170x5
Bench 195x5
and plateaud on everything so I switched to a 5 day split hypertrophy routine for about 3 months
Monday-legs
Tuesday-Chest
Wednesday-Back
Thursday-Off
Friday-Shoulders, traps
Saturday-arms

I've seen little to no gains and lost a couple pounds and all my lifts went down for example
squats 260-215
Bench 195-165
But all my lifts that I did on my hypertrophy routine went up. Is this normal? And switching back to SS Btw

[thousandmiles]

So I did Starting strength for about 8 months and got to
Squats 260x5
Deadlift 305x5
Military press 120x5
Power clean 170x5
Bench 195x5
and plateaud on everything so I switched to a 5 day split hypertrophy routine for about 3 months
Monday-legs
Tuesday-Chest
Wednesday-Back
Thursday-Off
Friday-Shoulders, traps
Saturday-arms

I've seen little to no gains and lost a couple pounds and all my lifts went down for example
squats 260-215
Bench 195-165
But all my lifts that I did on my hypertrophy routine went up. Is this normal? And switching back to SS Btw

no it's not normal
why didnt you just progress like a normal person