Delphi was great for developing custom solutions for middle class companies. Not end-user stuff, but no enterprise either. That kind of software vanishing coincides with that whole business sector getting smaller.
From a technical perspective, it was my favorite attempt to tame a often horrible mess of half-baked database design and ad-hoc solutions -- you can do spaghetti code in every language, but the Delphi apps I saw were usually a bit better than their FoxPro/Access/FileMaker/VB equivalents.