When the very first Les Paul was introduced in 1952, the degree of the neck angle was not properly set to account for the height of the guitar's maple top.
It is believed that the original design was without a carved top, and thus a Les Paul Junior style neck angle was used. However, leading up to it's release, it was suggested that a carved top be added.
My guess is that tooling had already been made and it was easier to mill the tailpiece bridge so that strings wrapped under?
This is truly a fact that puzzles me to no end. Especially when you consider that this was coming from a company synonymous with building such amazing instruments. The fact that they accepted this oversight for over a year and a half of production is truly puzzling. Not to mention the fact that the instrument's endorser, Les Paul, was known among other things, for his "Palm Muting" technique.

With this, the trapeze tailpiece bar had to be made in such a way that the strings wrapped under it to achieve proper action. A little over 1.5 years passed and the design was adjusted in two ways; a slightly steeper neck angle, and a thin eared wrap tailpiece mounting to two anchored threaded studs.

For years, countless trapeze gold top's were modified/converted/butchered to fix this issue.
The first time I saw one with a super thin retrofitted bridge was in late 2007 on Keith Urban's unbound '52 gold top, done by Nashville repair legend, Joe Glaser.
This style modification looks great and uses brass; however, is highly custom in nature and not readily available.

Enter the MojoAxe compensated top-wrap trapeze tailpiece. A fellow enthusiast, Dan of MojoAxe filled several gaps in the vintage guitar world.

Pictured below, are two tailpieces of their’s I use regularly.
The wrap-tailpiece on the left has a discrete yet effective milled ridge along it's length, allowing for greatly improved intonation.
The trapeze tailpiece on the right, lowers the trapeze assembly thus allowing the desired action to be achieved and more importantly, strings to wrap over the top of the bridge.