But it can also have a different effect. If you don't reply, the requestor does not know if you even read the message, so they might try resolving the problem by themselves. However if you say "I'm busy, will check later" they know they don't need to even try, as you are going to resolve the problem for them. That's the best case. Worst case, they'll report to their manager that you're "blocking" them and they aren't able to work for the next 30 mins because of you.
> they know they don't need to even try, as you are going to resolve the problem for them
It's unlikely that the team is best served by you treating your coworkers like children who you are responsible for teaching.
> Worst case, they'll report to their manager that you're "blocking" them and they aren't able to work for the next 30 mins because of you.
If you are, what's the problem?
And in either scenario, responding "bit busy, will check in 30 mins" both allows short lived transient problems to fix themselves, and lets the sender know that yes you got their message and that you can not look at it now but you are not ignoring it either.