I've been meaning to ask in your profession, is covid going to become milder and milder with subsequent mutations to the extent that we need not become too concerned and it would be most unlikely that a severe mutation will come from
I think the epidemiologist community thinks that is kind of a myth. Since mutations are random, a more severe variant can appear. Whether it becomes the dominant variant is super complicated, nobody can say for sure it will become more mild.
On why Omnicron evolved to be more mild than Delta:
The Omnicron is more "Mild" because tends to replicate first in the nose/bronchus/upper airways, whereas Delta is more "Severe" because it tends to replicate first in the lower lungs/lower respiratory system, which deeper infection is more likely to trigger an systemic inflammation (cytokine storm) in which your body overreacts and attacks yourself. More likely to get long COVID due to lung damage too. Also, Getting Bronchitis via Omnicron is way better than getting Pneumonia via Delta, which explains why hospitalization is reported to be lower for Omnicron compared to Delta. It also explains why Omnicron has increased spread/transmission (infects the nasal area/upper airways) compared to Delta.