Unless you jailbreak the issue is muted. That is, your apps come from iTunes and tested there.
I have yet to see a patch for Windows XP.
Can you share if you did jailbreak or not? If you did that, you accepted the risks as well as the issue that Spectre and Meltdown have not shown up on iOS (not jailbroken) yet. I think the media is playing on your fears.
Just wondering why Apple is not providing patches for this problem to older ipads and iphones that are not able to update to IOS 11. They are still very usable, many folks are using them, and they are vulnerable too. Microsoft is providing patches for older systems, why can't Apple too? Why don't they feel the responsibility to the millions of users out there that have and use these devices on a daily basis>