I don't believe D7 is abandoned. Drupal 8 has a long way to go before it will be ready for many sites, as there is a need for a lot of modules to be upgraded for Drupal 8. I just got PHP7 and D7 is running just fine on it, only one small hiccup with the editable_fields module and we're set. I was hopeful that I would see a dramatic increase in performance as I had heard was possible with PHP7. I do see a slight performance increase, and I confirmed that I am running it with opcache enabled. But I'm a little disappointed, it seems that these results for Drupal 8 are accurate. So, now I will work on installing HHVM to get that boost I believe is available. My results with Drupal 7 on PHP7 look like what I see here kinsta blog post : the-definitive-php-7-final-version-hhvm-benchmark for Drupal 8.0.1, so I'm hopeful that HHMV will perform as shown here with D7.