Yes it’s been known for a long time, digital releases with many release events slow down the site. You can check Digital releases: Merging? / Long country list? / Just [Worldwide]? for a long discussion around the topic.
The consensus in these cases (as far as I’ve seen) is to set these releases to either worldwide or leave the release country blank, to avoid spamming release events.
That release you linked seems to only be unavailable in Puerto Rico and the British Indian Ocean Territory (see Harmony cached page) it’s available everywhere else. It’s up to you if you want to set it to worldwide or leave it blank, but either is preferable to 100+ release events.