No it's perfectly irrational, because Nokia is not a platform vendor it's a phone vendor. A Nokia Meego phone sale is not stealing Lumia sales it's stealing Samsung/Apple/HTC/LG/Motorola sales. Nokia hardware is not here to sell software platforms it's an end in itself. Every Nokia competitor understands this and will use any software platform that will help it sell its hardware, platform purity be damned. None is single-platform (except for Apple, but then Apple controls its software well enough to make sure it will fit its future hardware products).
That's why Nokia is on a death march today: Elop decided it was more important to sell the products of its partner than to sell its own.
Windows Phone is not developed at Nokia but at Microsoft. No amount of Meego/Symbian killing was going to make Windows phone improve faster. OTOH the direct result of this killing was Nokia's inability to deliver differentiated phones (a must for a mass-market vendor, not for a niche player like Apple that focuses on the high-revenue segment). There is little difference between Lumia models because they are all declinations of the same Windows reference platform, that is too immature to permit much hardware differentiation (or even to keep compatibility with older hardware platforms, see how the current Lumia line has been obsoleted by Windows platform changes).
On a PC platform it does not matter much what the hardware is because of wide compatibility. In the embedded world if software and hardware do not fit you have nothing to sell.
The Series 60/Meego was not massively hipped but it *was* a massively profitable. The Lumias have been massively hyped (with record marketing expenditures and astroturphing) and try to emulate another massively hyped product line (Apple's) but they're not bringing any revenue. Now if you want to measure success in app store submissions Lumia is a stunning success. I'll take real users and real money any time.