Election winners are never determined by candidate concession speeches. Whether or not any candidate does or does not concede an election has no legal effect, under the law, on final election outcome. Even if there is a close recount, the win goes to the candidate with the most votes. There are even laws to determine a winner, should there be an actual tie.
Candidate concessions are matter of maturity and politeness…not a legal requirement. So all of the rhetoric about this issue is truly just political nonsense concocted to deflect attention away from other issues and upset folks who are sorely in need of some civics lessons…..just saying.