That Views import/export facility is no longer available in Drupal version 8 (within "
A possible way to do similar Views imports/exports in Drupal version 8 is to use the new configuration management facilities, which can typically be used to migrate configuration items, such as Views, between related dev, staging and production sites.
So it appears to me that as of right now (8.0.5) there is no "easy" way (as it used to be in Drupal version 7) to do such imports/exports between 2 sites that are not "related". Except probably/maybe with some special manual editing to make the site Ids match somehow.
Though according to Berdir's comment below (excl. some typos), "that's not true. You can use single import/export of any configuration file between any site, as long as you take care of the dependencies as well. The related site/UUID checks only apply to a whole config sync.". And followed by the
/admin/config/development/configuration/single/import suggestion (merci Berdir).
Maybe an opportunity for a new D8 contributed module to bring this import/export facility back ... and/or one of the "reasons to be" for the Features module in D8 (as suggested in another comment by Danny Englander) (merci Danny).
PS: For some more info about
/admin/config/development/configuration/single/import mentioned above, refer to the Community documentation about "Managing configuration in Drupal 8". Part of what is included on that page is like so (bold markup added here):
It is possible to export a single configuration file and paste it into another environment. The single import option lets you specify the type of the configuration file and import it from your copy-pasted value.
Though nowhere on that page I could find an indication if using "environments" for which site Ids are different (for "single" imports) is allowed or not.
If you want to get an idea of how it is like to use these import/export features, then have a look at the slideshow "The Magic of Drupal 8’s Configuration Management on a Managed Workflow" (especially slides like on page 44 to 48).