Judging by WALS and PHOIBLE, you're not wrong. I also like to avoid them where possible.Isfendil wrote:Also, I usually don't have [ð] and/or [θ] in a conlang unless they're allophones or they're a big part of the family (my nascent semlangs come to mind). I was always led to believe they were weird, uncommon sounds that liked to dissapear. Was I wrong? And are they really that common, given that an individual conlanger's languages may be in their own conworld and not ours, and therefore not add to our world's census total of languages with those phonemes?
Anyway, here's two conlangs with interdental fricatives or approximants*:
[o̞:l xju:man bi:jiŋs ar bo̞:rn fri: and i:kwal in digniti: and raits | θei ar e̞ndaud wiθ ri:san and kansje̞ns and sjud akt to̞:rds wan anaðe̞r in a spirit af braðe̞rxud]
[äɬ hijumän̪̥ b̰ḭjḭŋks äɾ̥ b̰o̞̰ɾn̪̥ pri än̪d̪ ikβ̞äɬ in̪ t̪iɣ̞n̪it̪i än̪d̪ ɾäits | ð̞e̞ äɾ̥ e̞n̪d̪aut̪ β̞iθ ɾisän̪̥ än̪d̪ kän̪ʃe̞n̪s än̪d̪ ʃut̪ äkt̪ t̪o̞ɾts β̞än̪̥ än̪äð̞e̞ɾ̥ in̪̥ e̞ e̞spiɾit̪ äɸ b̰ɾä̰ð̞e̞̰ɾxṵt̪]
* - but there's a well-motivated a posteriori reason for them to be there! I promise!