It's not a perceived advantage, it's a statistically proven advantageClarification C of the handicapping rules acknowledges the issues of larger fields and the make up of the fields' handicaps with a recommendation that playing handicap allowance should be reduced below 95%.
But, as discussed historically in a different thread, the national unions chose to ignore this and go with a mandatory blanket 95%. Reducing it to 90% or lower for larger fields would give higher handicap golfers less of a perceived advantage.