So let's see some examples then.
Why is LibreOffice "absolutely dreadful"?
In GIMP, where are the layer groups? The nondestructive editing?
These are basic tools to a professional workflow.
And don't get me started on CMYK. You cannot do prepress without CMYK support; GIMP was going to get it Real Soon Now for the past ten years and it's still not there.
GIMP is the story of what happens when you wait with new features until "the right solution" is completed. Not that I really blame them since they have very few developers.
pivot tables and VBA sucks (you may NOT comment on what a horrible language VBA is. )
I didn't ask which of the programs in the Microsoft Office suite is better than the programs in the LibreOffice suite, I asked why LibreOffice sucks.
Also LibreOffice has Python.
LibreOffice is much the same, but I think the gap is actually much smaller. Microsoft Office does have some niche features that are not replicated by LibreOffice, and Microsoft has made their formats for annotations and other features that should be simple sufficiently complex to make import/export difficult, but LibreOffice in my experience is faster and has more of the features that I like and use (at least more accessible; apparently someone has said Office now includes direct PDF export, so that's nice). I use LibreOffice even if I'm using a computer with Microsoft Office installed. As with GIMP, in some specific cases, Word may be required, but in most cases LibreOffice works just fine and saves you hundreds of dollars.
The exception here is probably Calc v. Excel, because it seems true in my experience that Excel has many more features for power users than Calc.