Getting your TLD approved by ICANN doesn’t mean it will go online.
Section 1.2.3 of ICANN’s Applicant Guidebook for new TLDs points out a stark reality for new TLDs: they may not work. Worse, they may work in some places and systems and not others:
All applicants should be aware that approval acceptance of their applications by ICANN and entering into a registry agreement with ICANN does not guarantee that the new gTLD will immediately function throughout the Internet. Past experience indicates that network operators may not immediately fully support new top-level domains, even when these domains have been delegated in the DNS root zone, since third-party software modification may be required and may not happen immediately.
Similarly, software applications sometimes attempt to validate domain names and may not recognize new or unknown top-level domains. ICANN has no authority or ability to require that software accept
new top-level domains although it does prominently publicize which top-level domains are valid and has
developed a basic tool to assist application providers in the use of current root-zone data.
Since top level domain additions have been few and far between this decade, I can imagine resistance in the software community to an onslaught of new TLDs. It seems that ICANN should work with major software providers such as Microsoft, Mozilla, and e-mail systems to ensure they will support the introduction of new TLDs en masse.
It kind of reminds me of mobile SMS short codes (e.g. text “VOTE” to 112233). Whenever someone registers a short code, they have to get approval by each mobile carrier for phone customers to be able to actually use the short code on their network. Can you imagine trying to convince Microsoft of the importance of your new domain?
The guidebook continues:
ICANN encourages applicants to familiarize themselves with these issues and account for them in their startup and launch plans. Successful applicants may find themselves expending considerable efforts working with providers to achieve acceptance of their new top-level domain.