Tableau is currently limited to displaying 16 dimensions columns in a cross tab. There are no workarounds to this limit.
To quote Ben Schneiderman's Information Visualization: Mantra "Overview, zoom & filter, details-on-demand"
Those details on demand may included more than 16 columns. When it does, users of Tableau should expect their software to deliver for them.
I don't know what the magic number of text columns should be, but 64 sounds reasonable to be released in the next version.
*16 columns before Tableau forces concatenation of columns.
-->Community Manager update Apr 5 2019 [Ciara Brennan]
Also refer to Duplicate Idea #3554 https://community.tableau.com/ideas/3554 ( 5 Votes )
Status changed to "In Review", as per request by Harveen Kathuria