Considering hashrate is at 100TH/s and annual profit mining is $9,200, the switch to solo mining is more a position in statistics than a trip to the casino. Take into consideration that another Antminer S19j Pro is added and you cut that 25 years of timespan in half. This miner acquired again and we see the likelihood of block reward be reduced down to 6 years.
And during that '6 years' you are paying for over 3,200w of electricity being used 24x7x365x6. That makes for one helluva electric bill to be paid each month with zero income unless you are very very lucky...