I removed them in a recent condo remodel. we also opened up a wall and put in a half wall / bar type of configuration.
When these are removed it is generally done with a whole cabinet removal / gut type of renovation. Removing the soffit when the cabinets are still in place is not recommended
...We had our soffits removed when we had our kitchen redone after a kitchen fire.We put in new cabinets that went up to the ceiling. I Iove all the extra space now but it was a lot of hard work. The kitchen had to be rewired because the wires were stretched tight in the soffits.And new drywall put in.
Not hard to do, bigger soffit = Bigger hammer. But you need to do some research on this before you take out your frustration. Some soffits are structural and supporting your cabinets. And removing them will have undesired results. Also some soffits hide air ducts, pipes and all sorts of other ugly things you will not want to have to deal with. So if you can open up one end as small as you can and using a flashlight and your eyes take a look to see what hidden treasures may be unwillingly discovered in that valuable space.