Not quite true. Thunderbolt 2 is backwards compatible with 1 so the old Thunderbolt Display from Apple still works, as do other TB devices. Thunderbolt 2 also brings us DisplayPort 1.2 which is a bit more interesting when it comes to displays. Dell has quite a collection of such displays. Thanks to DisplayPort 1.2 you can daisy chain them (like firewire and Thunderbolt, DisplayPort 1.2 supports daisy chaining). Lastly it also supports 4k displays.
When it comes to displays there are quite a lot that can actually take advantage of Thunderbolt 2. The only problem is that they can't fully take advantage of Thunderbolt 2. However, if we are very realistic about it that won't be a problem. The Thunderbolt Display doesn't need Thunderbolt 2 to function; it would if it were 4k. You can also put the Thunderbolt Display at the end of the chain, just like with any non-Thunderbolt display (for example: Dells DP 1.2 displays). Also, currently there aren't that many Thunderbolt 2 devices around, but they are coming. 4k displays are also in its infancy (look at price and refreshrate) but they are available and usable. If you want such display and need to put it at the end of the chain there will be a problem. However, both the MBP Retina and the Mac Pro have more than 1 Thunderbolt 2 port.
Currently the biggest problem is not the displays but your Mac: it has to support Thunderbolt 2 and not all of them do...yet. We just need to wait a bit longer I suppose.