Having used both MS and Borland products during the late 90s and early 2000s, Borland tools were definitely far superior from the standpoint of ease of use, time it takes to develop serious applications etc.
The primary advantage of the Borland's tools apart form itse its ease of use and was its very interesting component architecture which allowed for very easy development of third-party components and so many high quality third-party components were available free or at low cost. While this was happening MS got lost in the bushes trying to get ActiveX, COM etc to be the bridge for component inter-usability but it didn't come close to the ease of development of components in Delphi, CppBuilder etc.
The issue with Borland was the poor quality of management after their founder left. They tried to get into the Application Development Lifecycle space, bought up a lot of companies in that space and increased the cost of their dev tools to the point that it was no longer affordable to smaller dev shops who were their primary customers.
This problem hasn't gone away. Embarcadero still has ridiculous pricing for their products even though now they have a very stripped down IDE which can be used for free till you hit the USD 5000/year revenue limit.
We used both at university, for designing UI and corresponding events Borland's dev studio was easily 10x faster to design if your UI was a bit more complex, especially if you are not very familiar with whole ecosystem.
MS design of their stuff in those years was often... shitty on multiple levels to be polite, ie MFC comes to mind, over-complicated for no good benefit. People jumped to literally anything else if they could, be it Borland for C/C++, Java had much saner object-oriented design model too (which could be compiled to native code with native UI if needed, since their default stuff didn't look the best).
The primary advantage of the Borland's tools apart form itse its ease of use and was its very interesting component architecture which allowed for very easy development of third-party components and so many high quality third-party components were available free or at low cost. While this was happening MS got lost in the bushes trying to get ActiveX, COM etc to be the bridge for component inter-usability but it didn't come close to the ease of development of components in Delphi, CppBuilder etc.
The issue with Borland was the poor quality of management after their founder left. They tried to get into the Application Development Lifecycle space, bought up a lot of companies in that space and increased the cost of their dev tools to the point that it was no longer affordable to smaller dev shops who were their primary customers.
This problem hasn't gone away. Embarcadero still has ridiculous pricing for their products even though now they have a very stripped down IDE which can be used for free till you hit the USD 5000/year revenue limit.