BB has changed their placement policy from time to time. In the USA, they generally had not placed teams in D.III; then last season did for a while, and then stopped, and have been replacing bots this season.
I think it is good that they are willing to place new teams fairly far up, In the smallest countries, even starting teams out in D.I. But it certainly wouldn't be fair for a new owner to replace the current bot team in the NBBA.
Rather than being unfair to the new teams, I think it may be more of a question of unfairness to existing teams who were placed in lower divisions. To the extent that bots are replaced in D.III they will block extra promotion opportunities for teams in D.IV.
Perhaps they could take into account how many teams a new team was being placed in front of. For example, have a rule that a new team can't be placed ahead of 1/4 of existing teams. For example Germany currently has 556 teams. There is a capacity of 336 teams in the top 3 divisions, so there are at least 220 (556-336) D.IV teams. Any team being placed in D.III is being placed in a better financial situation than 40% or more of German teams who signed up first.
Or more radical would be to consider promoting teams from D.IV during the season. At the end of last season, there was a priority list created to determine which additional teams from D.IV promoted to D.III. So there are teams that just missed qualifying for promotion. Let them decide whether they would accept a mid-season promotion. If a team becomes a bot in D.III, then swap teams, with each taking over the other team's record and schedule. If you run out of D.IV teams that want a mid-season promotion, then you could start placing new owners in D.III.