This new update from Joomla will produce a more SEO-Friendly URLs. The stable release of the update is not until the second week of September, but Joomla site owners can start the test changes.
In the new routing system, router defines a new and more flexible interface for developers to handle creating and processing URLs and gives end users more options as it relates to how URLs are displayed. The new routing system will generate a cleaner URLs for your pages.
The number 150 has no meaning both for the readers and the search engines. Joomla 3.8 routing system will remove the ID number to create a much pleasant URL.
Joomla 4 Compatibility, the upcoming Joomla 4 core architecture will be supporting and largely using namespaced PHP code. To add compatibility with the new namespaced classes in our libraries directory, starting in 3.8 the majority of the library classes now use the namespaced class names and the existing class names are still supported through the use of class aliases.