Airtel gives 110% of speed always, there's no headache of it going down and then not fixing it. Jio on other hand gives 95% promised speed and there no real guarantee + they point you behind a NAT.
In case your Happy with less speed you can downgrade to 100 Mbps (120 Mbps) plan at 999₹ or even 40 (55 Mbps) plan at 499₹.
Instead I would suggest, upgrade your old phones to new phones like
Redmi Note 10 which support wifi calling.
In short term my advice might not be that appealing but in long term it will make sense.
In today's world without internet feels like being cut off of oxygen. Not having to worry if the internet will go down or not is a huge plus.