Maths says no.
I ran 10 Torment 16 Nephalem Rifts solo with a max rank Boon of the Hoarder gem equipped.
Gold before the T16 runs
12,084,127,220
Gold after each successive T16 run…
- 12,211,264,188
- 12,315,579,972
- 12,531,762,392
- 12,651,267,008
- 12,797,256,736
- 12,910,848,472
- 13,035,837,536
- 13,186,542,323
- 13,320,962,383
- 13,470,474,723
Okay, so the gold earned was…
13,470,474,723 - 12,084,127,220 = 1,386,347,503
At Torment 16, the Guardian is guaranteed to drop 3 GR keys, with a 50% chance of a 4th key.
That means, on average, running 10 T16 rifts will result in 35 GR keys.
Okay, so that brings us to running empowered GRs.
You said you’re running empowered GR105s.
Gold cost to empower a GR105…
96,000,000
Gold reward from completing a GR105…
32,032,586
Net gold cost to run an empowered GR105…
96,000,000 - 32,032,586 = 63,967,414
Net gold cost to run 35 empowered GR105s…
35 * 63,967,414 = 2,238,859,490
Gold earned whilst farming 35 GR keys = 1,386,347,503
Gold spent whilst running 35 GR105s = 2,238,859,490
That’s a gold deficit of…
852,511,987
In order to break even, the net cost to run 35 GRs has to be no more than this much per GR…
1,386,347,503 / 35 = 39,609,928
The gold reward for completion of a GR is approximately a third of the cost to empower it.
That means to break even the cost to empower each GR can be no more than…
( 39,609,928 / 2 ) * 3 = 59,414,892
The cost to empower GR89 is 59,000,000
The cost to empower GR90 is 61,000,000
So, running T16 Nephalem Rifts, even with a max level Boon of the Hoarder, will only supply enough gold to fund the empowering of GR89s. Once you’re empowering GRs at any level higher than that, and you’ll run out of gold very rapidly.