Today, US based file sync & share vendor Kiteworks announced their acquisition of ownCloud and Dracoon. Nextcloud offers a free hands on migration service and takes over the remaining runtime of the contracts. Migration is a very quick and easy process, as shown by the many hundreds that have done this already over the last years.
They developed OwnCloud Infinite Scale though. A complete rewrite in Go. And it runs pretty well and much smoother than that PHP abomination.