Why are horse collar tackles not ejectable?

I saw an NFL game recently where a horse collar tackle saved a touchdown. I would almost prefer a touchdown being awarded plus ejection.

Rugby has similar rules where rule breaking resulted in preventing a try so they said why risk or waste time just give them the score.

NFL is also looking at getting rid of hip drop tackles. Example used was the one done on Mahommes in the playoff last year.

I am a fan of ejections especially with player safety type rules. Not so much for the next game. I don’t agree with those unless a review later confirms it. Don’t allow appeals just allow a panel within the conference or nfl to review the penalty.
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