All have been abused by "marketing" to the point where they almost became or become useless. In some cases, workarounds were found so we can continue living our lives without spammers.
I suppose it's inevitable that push notifications are no different. But the argument is still unconvincing.
It's not inevitable that a tool with a glaring technical flaw must always have that technical flaw. Technical flaws can be fixed.
How hard is it to accept that for a lot of this stuff, there is literally nobody that wants to recieve it. It's fly-tipping your junk into millions of people's gardens in the hope that 0.001% of them see it and it reminds them of something they had meant to do already... The tech you are talking about almost certainly raises this to an amazing 0.0012%, by the looks of it it primarily does this by changing around the composition of the trash heap occasionally.
Until you invent telepathy, you will never be able to know who those vanishingly few people where recieving useless junk would remind them of something are