Starting with a file with one sheet, data in contiguous array (15 columns, 10000 rows, but these numbers are not critical for the issue), no formulas or external connections. When the array is formatted as a table, scrolling through the data (with scroll wheel on mouse or with scroll bar) becomes very slow (taking between 1 and 10 seconds for the app to become responsive again). The CPU utilization rises sharply from less than 1% to more than 30% during this period. Converting the table back to an array restores normal responsiveness. These steps can be repeated with same results: formatted table: very slow, array: snappy. This behavior started a few weeks ago, presumably in version 16.0.12827.
Tried safe startup, disable all add-ins, fix Office installation; no influence on behavior.