Why not Wix, indeed?
Many site builders are fine products and suitable for many people. Heck, they have millions of users and, for the most part, work just fine.
[We’re not picking on Wix, they just happen to be the best known of the all-in-one site builder tools. We’re using them as more of a generic term to encompass the various services — Squarespace, WordPress, GoDaddy and too many more to list — that offer drag and drop website building, often bundled with domain registration and hosting, in exchange for a reasonable monthly fee. ]
There are, however, some significant downsides to using site builders and managed hosting.
We’re somewhat biased since part of our business is moving people away from site builders, but there are a few issues that come up frequently doing these jobs.
Vendor Lock-in
Site builders offer the ability to get an attractive site online with minimal upfront costs via (usually) a drag and drop builder and word processing like text entry fields.