Since Ventura doesn't support hiding of startup apps no more, I made this simple AppleScript to hide 'em
-- Hide startup apps
repeat 5 times
tell application "System Events"
get name of every process whose visible is true
set All_Visible_Processes to result
if All_Visible_Processes contains "App1" then
set visible of process "App1" to false
end if
if All_Visible_Processes contains "App2" then
set visible of process "App2" to false
end if
if All_Visible_Processes contains "App3" then
set visible of process "App3" to false
end if
get name of every process whose visible is true
set All_Visible_Processes to result
if All_Visible_Processes does not contain "App1" or "App2" or "App3" then
-- beep
exit repeat
else
delay 3
end if
end tell
end repeat
-- include this script in a startup macro ("At Login") and you'll be fine (I hope so).