Why do you assume the microwave & food manufacturers would take the time to generate a whole database just for your convenience & at no profit to themselves?
Oh come on. Have you been living under a rock?
They spy on you and advertise at you of course. If that model doesn't work they then, after your already paid for the microwave, charge you a subscription to use the service.
Taking the example of frozen pasta ready meal, they can be a right pain. I will typically take the stated "first heat" time and put it in at 66-75% power for that time, not HIGH. By then it is usually stir-able, it's also pretty much defrosted. Stiring the hot parts into the frozen parts hurries that up. If I can't stir it or don't want to, I will probably run it the entirety of their stated "second heat" timer also at 60-75%. However, if it's stirred and defrosted, 1 minute on high will get it to "barely warm enough" and 2 minutes on high gets it to hot enough to eat with some parts a little frazzled. I like to heat my food so I can immediately eat it. (assume it's already cooked). I have never burnt the scare tissue into my mouth that others have, so I have no tolerance for "piping hot food", it simply hurts and literally burns me.
That said... risk... The other factor to consider why they tend to over do the cooking is that they specifically want to boil the food. They don't just want you to heat it up to eatable temps ~60-70*C. They want you to pin it at 100*C for at least a while.
Why? It will save them about 25% on their public liability insurance if they have lab tests showing this will significantly reduce the changes of any bacterial contamination making it to the customers guts.
Additionally, this allows them to put MORE water into the product. In the knowledge they are asking you to microwave it 2 or 3 minutes longer than is necessary, that excess will boil off. If you short cut the times on these meals they are sloppy. More water = more weight = higher price.
Tagent: Where I have found the most significant gains with "ding ding" cooking, is when it's used in combination with other things like grill or oven. This also tilts towards the "smart ovens" future potential.
Example: Frozen Pizza. Microwaved alone... you'd need to be desperate. Oven alone and typically the surface cheese is burning before the centre has fully defrosted and the centre is left soggy and sloppy. My technique is to pre-heat the microwave with it's fan oven to 230*C. Then put the pizza in on a stand so it's mid oven and use the "Pizza Auto" mode set to 400g. The automatic pizza mode uses a combination of oven, grill and short pulses microwave and produces the best looking and eating frozen pizza I have seen! Those short bursts of microwaves are just what it takes to rapidly defrost the core of the pizza while the oven is working on bringing it up to temp and browning it. The microwave basically get the pizza from 0 up to 100 and then the oven and grill do the browning.
Similarly, defrosting in microwaves. They go banded as being "ideal" for defrosting and I honestly have no idea why. Microwaves do not heat up ice. The hydrogen atoms held in the crystal latice do not transmit their resonance anywhere near as much. So what actually happens is, the part where your hand was holding the frozen item when it went in has got a small amount of defrosted water at just that point. That water takes the whole whack of the 900W -loses. It boils, it runs off into the tray and continues to boil the food from underneath, all while the mass bulk of the thing is still frozen and absorbing sod all microwaves. The approach of "pulse" and wait.... "pulse" and wait.... "pulse and wait...." will either take hours with only 1 or 2 second pules and minute or it will partially cook bits of the food (say a lump of steak).
However, what I now do is put the oven into "Convection + Microwave" mode. Which is about 10% microwave, 90% 2kW fan oven. 3-5 minutes. By which time the oven cavity is up to about 60*C, some of the food has been lightly and infrequently microwaved. Leave it alone for an hour and when you come back it will be perfectly defrosted and have virtually not rubberised leather, boiled grey meat to cut off.