.tel is a long-term speculative investment. Buyers are betting on the odds that .tel will become the default contact info directory for individuals and businesses, much like the white and yellow page directories used to be. It may prove viable and successful, but probably will need approximately 10 years or more to mature and succeed. At $11/year, it's probably worth the investment.
LOL, if you think it will take 10+ years to suceed even with $11/year, better invest on something else as you said speculative investment.
Everytime a new domain ext. launched, everytime is the same (.me, .pro, .ws, .tel, .biz, .blahblah...) domainers are the first to speculate it and feel as great investment until a year or more than they sell it all some sold for great prices and some for dollar, because it's just not as valuable as .com.
I admit that some record sales in .tld can be done with generic but most have DNS that can be customized to website hosting. with .tel you can't and this is a good thing and not depends on how they promote it.
Within 10 years new kind of web will appears like web 2.0 and now web3.0 (social websites...).tel will be obsolete if development stays as a directory style.
Also their project were 10 years old before they launch according to some domaining news if I'm correct, so in the 90-2000 it could be interesting because of low speed internet at this time on several places in the world and email was something people uses a lot at this time it was trendy and useful (fax became dead). But now with social network and tweeter kind of communication, email is less something that's trendy but an old thing but still useful today.
I guess that some new TLDs can appears in 10+ years if ICANN accepts with new technologies similar to .tel but having all in one apps (social, web, email, contact, personal site, mobile app...)
So no, for me .tel and other tlds are not equal to .com
I still have one .tel or .me I'll keep it all my life because I like that domain but not because I want to be rich with it otherwise I spend my money on other things.