In fact, I added that I never used Dropbox to give context on my perspective. I am not sure that qualifies as 'flaunting that ignorance'.

Regarding the delta-sync feature: That is, in fact, a feature neither Nextcloud nor Owncloud posses at the moment. On the other hand, it would not be that beneficial to my use-cases since I rarely have large files within my synced folders and most of the time I have a GBit connection to my Nextcloud. So I guess I am missing not that much (at least with my current usage pattern).

Granted, for some use-cases, it is essential and bringing such a feature to all major platforms is not a trivial task. Yet I still wonder if protecting the implementation is necessary since the comments in the Nextcloud issue suggest that the primary problem the availability of the developer is (who might have an easier job if he could take a look at the Dropbox code, but ultimately he would have to write an implementation that integrates with his project).

And ultimately I wonder what makes people decide which service they want to use. For many people, it sure is the little friction you encounter during the setup of Dropbox. For me, it is not that much about the features of the client software but about the features of the larger system. Being able to host my own server is essential to me. Having an open source implementation is a nice add-on, which I value and made use of already. AFAIK those features are not available with Dropbox I seriously doubt my previous comment qualifies as flaunting ignorance.