Can I change the column width in the sumo cards

Columns adjust automatically to fit either the screen or the column name, but can't be manually adjusted to a specific size (like 50 pixels).  That Excel-like functionality doesn't exist.  With one exception: when a column name is long and is truncated by default, you can turn that off or on by toggling the setting found by hovering over the sumo column name:

That setting is only available to truncated columns, so you won't necessarily see it on every column.