Malwarebytes has fixed bugs that were causing performance issues in Windows 10 2004. Users who have installed the beta have stated that it has resolved their performance issues, even with the enabled ‘Ransomware Protection’ feature. Users need to check for new updates to install the latest version and its components package to fix these performance issues. Users should be beta version 4.12.73 with the 1.0.990 component update, as shown below.Latest version of Malware bytes beta version is 4.73.
Source: https://www.bleepingcomputer.com/news/microsoft/malwarebytes-fixes-bug-causing-windows-10-2004-performance-issues/