I'm not sure if any branching strategy helps supporting multiple software versions simultaneously. There is a reason why "rolling releases" are the default now.
For a short while it may work to just merge bugfixes to older versions. But after a while the changes to older versions need to be done independently. Implementing a fix for three versions will just take three times longer than for one version very soon.
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I've been pushing and using trunk for years. To think someone looked at the graph for git-flow and said "yes please" is madness.
That said, trunk-based is probably not great if you actually do need to support multiple versions of a piece of software simultaneously.
I'm not sure if any branching strategy helps supporting multiple software versions simultaneously. There is a reason why "rolling releases" are the default now.
For a short while it may work to just merge bugfixes to older versions. But after a while the changes to older versions need to be done independently. Implementing a fix for three versions will just take three times longer than for one version very soon.