SaaS is the bane of my working existence. Not something that I am willing to come to terms with (and I don't have to, not an easy road to that position, but well worth it for me). And they really aren't good for production type of machines, having an always connected computer to the WAN is no bueno at all.
Data ownership, depending on how things are done, typically there are certain "freedoms/ownerships" that people sign away, particularly if using any type of 3rd party "cloud" type of service (and given how entrenched these are getting in at the OS level, it will apply at the OS level as well, not just individual programs).
As to keep legacy programs around, mainly going to depend on what the activation (or lack thereof) is needed, but as far as older OSs go, I'm a firm believer in VMs. Now if the program uses GL for it's entire UI, that could be more of a tricky situation and require more resources compared to what most people think of with VMing. Now, this is moot if the program in question requires actually pinging an active server. If it has some kind of dongle, there may be hope for some extra time.
I would suggest for those that just have the optical discs of programs, that one creates ISO backups of the discs (and actually use disc authoring software, not archival/compression software, depending on length of file names, truncation could happen and that would render the ISO useless and names wouldn't match up during the installation process). Given that optical drives seem to be going the way of the dodo and ISOs are seen on most modern OSs as a virtual optical drive, it works just as well.
As to back ups, I prefer having my own, 1 onsite and 2 others offsite. Not as cheap, but there are certain sacrifices that one makes with 3rd party solutions and I have know at least one 3rd party solution be used as a vector for getting people infected (their data transfer software was used).
Now bare in mind, even though I am no fan of SaaS and will drop programs that adopt that approach, I do not have a problem with paying for software in general. There are just certain approaches to licensing that I will not accept and thus won't use the program. I tend to also use more manual tools and I stay away from more program specific tooling, thus going from one software to the next is easier and I try to save in more universal file formats as well, minimize how much is only in the proprietary format. I also now tend to switch to programs that have well documented open/robust plugin systems to were if something is missing for me, I can add in there or maybe get lucky and someone else had a need and made what they did available. But I have written some tooling from scratch as well. May not be as robust as what I was replacing, but it would definitely have what I needed it to have.
People should not be unwilling to move to different software. Programs/vendors do change in how they do things and if things don't match up anymore, should be willing to be able to move to another program. There will be some teething pain in doing so, but the willingness to attempt should still be there. But if people are going to expect a 1:1 seamless transition, that will never work out.