I recently purchased a house and have noticed the floors seem to sag in certain spots. I notice in the basement that there are several sections where the joists were cut and then extended via tecos to the sill plate. Presumably because the sill plate needed to be replaced. I attached a photo of a small section showing what I'm describing. The majority of my basement is finished and can I can peek into a little space to allow the plumbing to run and there looks like there is a long stretch of this seemingly hack. Note, there was a significant house fire hence why the joists were painted/sealed.
1) is this a legit way to repair joists/sill plates?
2) is this safe?