Can someone using Ubuntu 22.04.1 LTS with an Ubuntu Pro subscription with third party packages installed in seven years time expect to have the same level of security for those packages as someone who has the latest version of Ubuntu installed in 2030?
How would we know?
If you install third-party software that does not come from the ubuntu archive, support and security must be provided by the third-party…
regarding anything from the archive, you will indeed get 10y of support as advertised
So based on what you are saying I take it that there is no point in anyone relying on third party applications subscribing to this as security updates applied to these apps by the vendors may not be available for old versions of ubunto running over 5 years…
So you are better off to just keep upgrading to the latest LTS version every 5 years to avoid trouble. Not much point in it for a lot of users out there so…
It really depends on the third-party in the end, if you buy a mercedes but put shiny ronal sport-rims and recaro seats in it yourself, will you expect support from mercedes when your seats or rims break ahead of the 10y warranty mercedes granted you for the car ?
While there might be an opportunity to buy additional support for such specific cases from canonical in the future, this does not exist today.
… currently only software provided by canonical though the approved channels (canonical maintained snaps from the snap store, debs from the official archives (including universe now)) is supported by canonical.