There is only a certain window in the Planning Process where objections can be submitted. Each one costs €20.
Anyone who submits multiple objections is simply wasting their money, also they damage their own case as "20 objections - all from Mr. Murphy", will make Mr. Murphy look like a crank.
If the subject matter of the objection is frivolous and vexatious, then it will be dismissed anyway. So it shouldn't really be a concern.
The only possibility for frivolous objections is an objection to ABP, which will delay an application by a couple of months, but is the price to be paid for the comparatively high protection of property rights granted third parties in the Irish Planning Process.
If OTOH you are submitting multiple Applications, and they are all being refused - and you are blaming some person who is objecting to the Application each time, then perhaps they are correct and you are not responding to the reasons for refusal.
What precisely is this objector actually doing that you are concerned about?