There is no safe reverse breakdown current and damage is logarithmicly proportional to the total charge so it is the initial breakdown current which has the most effect. Hot carriers cause dislocations in the silicon resulting in lower hfe due to shorter minority carrier lifetime. This is similar to radiation damage and can be treated through annealing; maybe some space based design intended to operate in a high radiation environment tried this.
The damage is not as significant for junctions which are already doped to produce short minority carry lifetime like in RF and fast saturated switching transistors. The application matters also; it is unlikely to make a difference with power transistors operating at high currents where their hfe is already low or transistors used as switches with high forced beta.
It makes a huge and crippling difference where high gain at low current is required like a differential input stage. Bipolar input operational amplifiers damaged like this display an order of magnitude or greater increase in input bias current, the noise to go with it, and high offset voltage. For this reason, they usually include input protection diodes to limit the applied differential voltage. Monolithic matched transistors like the LM394 include protection diodes across the base-emitter junctions to prevent damage but this was not universal; the MAT01 from Analog Devices is unprotected.
So do not run your supply of high gain 2N5086, 2N5087, 2N5088, 2N5089, BC546, BC548, BC550, BC556, BC558, and BC560 transistors and Analog Devices matched transistors through a base-emitter breakdown test; it will ruin them for their intended applications.
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