Software development does aid in ones own ability to manage projects.
As an IT leader myself, I've seen and worked with many newly minted managers- and minted a few myself. I'm not going to try to classify managers here- but I will say that a good manager is a mix of many qualities- subject matter expertise, people skills, political skills- all are important. What does *not* seem to be important, across many managers I've worked with, is where and how those skills were developed. How they are applied is. If the manager is to be in charge of a highly technical IT environment, and that manager only knows a small portion of that environment, it will be harder- but, if that person has solid leadership skills, and is willing to do the homework, most of the 'downside' will be internal to the individual- they'll feel like they're drowning, for a couple of months, until they develop a network.
On the other side, some people just cannot break out of their mold- they're solid technology people, perhaps even gifted in a certain area- but lack people skills, or political savvy. Sometimes, a new manager will make the assumption that they're now the expert in everything, making themselves look foolish- and they seem to have no idea how foolish they look.
So, to get to your question directly- if you are considering a career in IT management, first assess your abilities in leadership- preferably, have someone external make that assessment, and determine if you have the requisite leadership skills first. After that, remember to stay humble and rely on your network- and you'll be on the right path. It's no detriment to be limited in a given skillset- IT is a huge area, with many sub specialties- and you will never be expected to cover them all more than superficially.
I'm making the assumption that the "software experience" you refer to is "hand coding software", or "the software that the company I work for might make" - and not specific pieces of software that are endemic to any IT department, like AntiVirus, Inventory management, CRM, Office tools, Document management, email, webserver software, etc. If this assumption is incorrect, then I absolutely think it would be a detriment to the manager's career in IT.
If the assumption is correct, then I believe the best option might involve seeking a position with a company outside of the tech space, like Law, Healthcare, Academia, etc., and of a significantly large size; where there may be several folks with specialized knowledge and responsibilities over their fields that could minimize your interactions with their areas of software.
I would generally counsel against this approach though, because IT management is generally a business function - and understanding your customers needs is a critical component of success in this career. An IT manager that understands the company's software is uniquely positioned to tailor his/her skills to the environment, which results in better process and prioritization. Demonstrating this ability at one organization after another is likely to advance the manager's career quickly, as any hiring manager would quickly see the obvious value.
So it isn't necessarily a roadblock, but it just changes the opportunities the manager might have to pursue.
No... but they had better have some tech skills (as you indicated) and some solid project management bonafides ( or be able to show me they are VERY willing to learn).