Thick clients often (but not always) represent years of development with features added over time to become a mature application. The newer web applications or ones written for other than Windows usually do not have the depth of features nor the maturity.
- Azure Data Studio vs. SSMS
- Visual Studio Code vs. Visual Studio 2022
One of the contributing factors is the lack of expertise and insight (particularly at Microsoft) for making their tools facilitate rapid application development (RAD). Nearly 30 years ago, a small team created the UI environment for Visual Basic (VB "Classic") with drag-and-drop I creation. Many other software companies, like PowerBuilder, tried to copy it. VB "Classic" (referring to the UI development environment, not so much the language) revolutionized RAD. Less time on repetitive, mundane UI hand-coding, and more time on business logic and database design. Or just less time from conception to delivery to production and a lot fewer UI markup language bugs.
Today's Microsoft, having shifted to .NET and primarily C#, has had lots of trouble just making the WinForms RAD designer work. The "script kiddies" who think the command line is the beginning and ending of a software development UI, do not have the understanding of the value of RAD.
So, it is no surprise that the "newer" tools often lack the depth of productivity that make the "thick clients" desirable. What Microsoft, and other software shops need, are those with the understanding of applying productivity to an application design and applying the value engineering concepts that support the return on development investment of significant productivity.