You are right, i created a blank type with not so many fields inside it and it also works for me.
Seems like i have to many fields. Have a look on my request i get a http 400 error:
GET http://localhost:4000/rest/objects/?filter=[{“$lookup”:{“from”:“framework.objects”,“localField”:“fields.value”,“foreignField”:“public_id”,“as”:“data”}},{“$project”:{“_id”:1,“public_id”:1,“type_id”:1,“active”:1,“author_id”:1,“creation_time”:1,“last_edit_time”:1,“fields”:1,“simple”:{“$reduce”:{“input”:“$data.fields”,“initialValue”:[],“in”:{“$setUnion”:[“$$value”,“$$this”]}}}}},{“$group”:{“_id”:“$_id”,“public_id”:{“$first”:“$public_id”},“type_id”:{“$first”:“$type_id”},“active”:{“$first”:“$active”},“author_id”:{“$first”:“$author_id”},“creation_time”:{“$first”:“$creation_time”},“last_edit_time”:{“$first”:“$last_edit_time”},“fields”:{“$first”:“$fields”},“simple”:{“$first”:“$simple”}}},{“$project”:{“_id”:“$_id”,“public_id”:1,“type_id”:1,“active”:1,“author_id”:1,“creation_time”:1,“last_edit_time”:1,“fields”:1,“references”:{“$setUnion”:[“$fields”,“$simple”]}}},{“$addFields”:{“public_id”:{“$toString”:“$public_id”}}},{“$addFields”:{“creationString”:{“$dateToString”:{“format”:“%Y-%m-%dT%H:%M:%S.%LZ”,“date”:“$creation_time”}}}},{“$addFields”:{“editString”:{“$dateToString”:{“format”:“%Y-%m-%dT%H:%M:%S.%LZ”,“date”:“$last_edit_time”}}}},{“$match”:{“type_id”:1}},{“$match”:{“$or”:[{“public_id”:{“$regex”:“test\\-test\\.test\\.test\\.asset”,“$options”:“ismx”}},{“fields.hostname”:{“$regex”:“test\\-test\\.test\\.test\\.asset”,“$options”:“ismx”}},{“fields.lifecycle”:{“$regex”:“test\\-test\\.test\\.test\\.asset”,“$options”:“ismx”}},{“fields.dns-external”:{“$regex”:“test\\-test\\.test\\.test\\.asset”,“$options”:“ismx”}},{“fields.crown-jewel”:{“$regex”:“test\\-test\\.test\\.test\\.asset”,“$options”:“ismx”}},{“fields.asset-type”:{“$regex”:“test\\-test\\.test\\.test\\.asset”,“$options”:“ismx”}},{“fields.asset-criticality”:{“$regex”:“test\\-test\\.test\\.test\\.asset”,“$options”:“ismx”}},{“fields.profile-name-id”:{“$regex”:“test\\-test\\.test\\.test\\.asset”,“$options”:“ismx”}},{“fields.pear-device-id”:{“$regex”:“test\\-test\\.test\\.test\\.asset”,“$options”:“ismx”}},{“fields.pear-hostname”:{“$regex”:“test\\-test\\.test\\.test\\.asset”,“$options”:“ismx”}},{“fields.os-version”:{“$regex”:“test\\-test\\.test\\.test\\.asset”,“$options”:“ismx”}},{“fields.mac-address”:{“$regex”:“test\\-test\\.test\\.test\\.asset”,“$options”:“ismx”}},{“fields.host-groups”:{“$regex”:“test\\-test\\.test\\.test\\.asset”,“$options”:“ismx”}},{“fields.ref-company”:{“$regex”:“test\\-test\\.test\\.test\\.asset”,“$options”:“ismx”}},{“fields.ref-location”:{“$regex”:“test\\-test\\.test\\.test\\.asset”,“$options”:“ismx”}},{“fields.ref-division”:{“$regex”:“test\\-test\\.test\\.test\\.asset”,“$options”:“ismx”}},{“public_id”:{“$elemMatch”:{“value”:{“$regex”:“test\\-test\\.test\\.test\\.asset”,“$options”:“ismx”}}}},{“references”:{“$elemMatch”:{“value”:{“$regex”:“test\\-test\\.test\\.test\\.asset”,“$options”:“ism”}}}},{“creationString”:{“$regex”:“test\\-test\\.test\\.test\\.asset”,“$options”:“ims”}},{“editString”:{“$regex”:“test\\-test\\.test\\.test\\.asset”,“$options”:“ims”}}]}}]&limit=25&sort=public_id&order=-1&page=1&view=render&onlyActiveObjCookie=true