scoreboard objectives add teamDeaths dummy
scoreboard objectives add deathCount deathCount
scoreboard players reset @a[scores={deathCount=1..}] deathCount
execute as @a[scores={deathCount=1..},team=BLUE] run scoreboard players add @a[team=BLUE] teamDeaths 1
execute as @a[scores={deathCount=1..},team=RED] run scoreboard players add @a[team=RED] teamDeaths 1
scoreboard players set @a teamDeaths 0
execute if score @a[team=RED,limit=1] teamDeaths matches 80.. run say 123
scoreboard players set @a teamDeaths 0
execute if score @a[team=BLUE,limit=1] teamDeaths matches 80.. run say 123