That's why platform indipendency is a really important thing (which Ardour, unfortunally, don't have).
There are definite tradeoffs involved in platform (meaning API, really) independence.
First, there are performance tradeoffs. When building for a single platform, it is possible to leverage that platform’s performance to the best effect.
Secondly, when building to multiple platforms, that do things in many cases in radically different ways (GUI toolkits, for instance, have very very different paradigms; GTK and Qt work very differently under the hood, for instance, and one of the most popular cross-platform open source GUI Toolkits, WXWidgets (used by Audacity) is different yet again), the developer either has to have completely different libraries for basic things (like the GUI event loop) or the developer has to take a least common denominator approach. And while GTK has been successfully ported to more than one platform, GTK is but one API that Ardour needs.
Third, true cross-platform compatibility is very hard to retrofit. Cross-platform support really needs to be an early design goal, when the basic cross-platform infrastructure can be designed in and not bolted on. Ardour is complex enough that making it cross-platform would involve a vast amount of work that the developers have said they aren’t keen on doing.
So if you want a true cross-platform DAW, my recommendation is to go bug the Audacity developers about making their program more DAW-like. Or join up with one of the other cross-platform DAW groups.
And, having said all that, I don’t consider Ardour’s lack of full cross-platform support to be unfortunate in any way whatsoever. [EDIT] And I’m talking about API cross-platform-ness; as Paul said, most of the basic APIs are highly portable, but some are not (Windows, for instance, has some really different ideas API-wise even in their ‘POSIX’ layer…).
What is really important is getting the work done, not what tools you use to get the work done…l Although I must admit I wish that I hadn’t sold my old UREI Levelling Amplifier years ago…some tools just have class Would love to see a good LA-2 sound-alike (don’t have to look like it, like the UAD plugins do) plugin for LADSPA/LV2
Although my RCA Audimax has much the same sound…