The old installation method, used with Matlab R2020b, highlighted several problems for some users. The solution was found in a different installation method. Some users will prefer the new method, others the old one. Each has its pros and cons. The new installation method makes Matlab easy to install, also for older versions and can be done with a small download if you only want a few toolboxes. But it requires signing in at The MathWorks and thus has a more complex workflow. The old installation method does not require registration and has an easy workflow, but it always requires a large download and non-expert macOS users will find it troublesome because the newest macOS version will quarantine the download.