> maybe t-strings can be creatively used here somehow

Maybe they could, but I would be the first to oppose introducing creative ways to do logging or string formatting.

Such basic things should be done in the most standard way possible to reduce cognitive effort required to read and understand the code.

But the standard way is kinda ugly. Most people would expect f-strings to be used for "normal" string formatting and %-style to be used for logging, because it is the default and most codebases do it this way. Therefore, you basically forced to have (at least) two different formatting syntaxes in your codebase.

I say "at least", because if the program serves html pages, you most likely also have some other template engine like jinja...