Imagine if gas stations showed the true price of their gas plus a few cents. You’d be pleasantly surprised when they charged you $1.97/gal instead of $2.00, but your ability to budget precisely would be adversely affected.
The fudge factor always existed, it is now the airline's job rather than mine.
They have an incentive to pick a good-enough one, while adjusting it daily/weekly while I tend to fly once every couple of months and that too to a completely new airport most of the time.
If you do the fudging right and leave enough padding, it makes everyone happy - if you pad too much, you lose business as several normally possible connections become impossible by the published schedule.
Indigo did this in India a few years ago and the flights were 30-45 minutes longer on paper (like a 90 minute flight marked as 120), but because of their on-time reputation they got a lot of business customers who take multiple flights a day over other airlines.
For myself, almost all of my connections are not within driving distance, and my schedule is usually unforgiving to overnight delays. I usually budget 2.5 h minimum for transfers, 3.5 minimum if entering the US because passport control has its own very large variance. Haven't had the inconvenience of a missed connection in the last 10 trips.