Can we say salAllahualayhiwasaalam out loud when mentioning the Prophet ﷺ in our notes so as to save space and time? Or is this from being lazy?

Yes you can say but as Imam Annawawi mentioned thay you get rewarded for it so don't get reluctant, and alhamdulilah everything is recorded so u can easily rewind 10 secs to write what u have missed.