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I own a 2012 Toyota Prius and it's working fine.  Should I get a new Tesla car to replace it?

There are 4 models of Tesla.
^Which^Type^Seats^Range^Price^Cargo space^
|Model 3|Compact Sedan|5|~272-363mi|~$39k-$47k|~24 cu ft|
|Model Y|Compact SUV|5-7|~260-330mi|~$44k-$52k|~76 cu ft|
|Model S|Luxury Sedan|5|~405mi|~75k+|
|Model X|Luxury SUB|5-7|~335mi|~80k|
My Prius has about 22 cu ft cargo space (seats up) or 39 cu ft (seats folded).\\ 
I would be most interested in considering the Model Y.

Compare cost per mile between 2012 Prius getting ~45mpg and Tesla Model Y AWD using realistic assumptions in Massachusetts.\\ 
Assuming: 
  * Gas $3.30-$3.50/gal
  * Electricity $0.30-0.34/kWh
  * Prius about 45mpg
  * Tesla Y AWD efficiency: 270-300 Wh/mile (which is about 0.27-0.30 kWh/mile)

Assume for calculations, gas $3.40/gal, Model Y 0.28kWh/mile, Electricity $0.32/kWh, super chargers $0.30-$0.45kWh

Prius\\ 
Cost per mile = gas price / mpg => 3.40/45 =0.076 or 7.6 cents/mile

Tesla\\ 
Cost per mile = kWh per mile * electricity price => 0.28 * 0.32 = 0.0896 or about 9 cents/mile.\\ 
Cost per mile using fast-charging 9-13 cents/mile

What this means:\\ 
Given cost of electricity, \\ 
Prius 7-8 cents/mile\\ 
Tesla 8-10 cents/mile (home charging)\\ 
Tesla 9-13 cents/mile (supercharging)
//in other states where electricity is cheaper and/or using solar energy, EVs would win out on fuel cost.//

Conclusion: Prius is usually cheaper to fuel.

Assuming 10,000 miles/year, approximate comparison:
|Prius 45mpg|~$755/year|
|Model Y AWD (home charging)|~$900/year|
|Model Y AWD (Supercharging)|$900-$1300|

Note also that EV ownership saves money in that: 
  * no oil changes
  * less break wear (due to regenerative braking)
  * fewer drivetrain maintenance issues
  * no exhaust system
But on the other hand, on a Tesla
  * tires wear faster
  * insurance is often higher
  * and then the purchase price

Insurance differences in Massachusetts
  * Prius hybrid: $1,000-$1,400/year
  * Tesla Model Y: $1,800-$2,600/year

Reasons switching from Prius to Tesla makes sense
  * Tesla has much larger cargo capacity
  * No gasoline costs
  * Smooth & quiet driving experience
  * Modern safety & tech features
  * AWD is convenient for our winters

Reasons that switching might not make financial sense
  * My Prius is very economical
  * Insurance for Tesla would be higher
  * Excise tax would be higher
  * Purchase price is significant