I don't care who it was. If it was Sandro he learnt from his past mistakes and if it wasn't, the new designer knows their stuff. Either way it's a big improvement.
I think you're misreading the nature of the 3.3 update. 3.3 was a gameplay overhaul rather than a content drop, so it doesn't reflect on grindiness either way. eg:
- Guardian ruins, engineers, etc: these were new systems that you could play (or grind) for equipment upgrades. Their grindiness is greatly influenced by an arbitrarily-decided number of how many times you must to do the task to get the carrot. 3.3 offers no such new paths to achieve new upgrade mechanisms, no way to know if the grind design has changed.
- 3.3 mining overhaul, 3.3 exploration overhaul, etc: these are the fleshing-out of early skeletal mechanics. They don't change the number of times you have to do the task to Get The Thing, but they offer you more buttons to push and more gauges to watch while you do the task, so any grind is not so obvious. So again, no way to know if the grind design has changed.
I get what you're feeling - that Elite became less grindy because of 3.3 - but that doesn't mean a change in design philosophy or different people or different visions, it's more just the nature of fleshing out a game mechanic vs adding a new-but-skeletal system.
Both types of update are necessary and will continue in the future, but one type highlights the grind while the other type disguises it.
You have to frame the walls before you can build the roof. You don't conclude that the construction team that built the walls must have got a better foreman because rain was such a problem while they were doing walls but now with the latest work on the roof the rain problem has stopped
(That said, I also suspect content drops will slowly become slightly less grindy over time, because as the game's foundations expand, each month of game production may be able to produce slightly more hours of unique gameplay, which means decreasing incentive to use grind to artificially inflate the hours required to play through each update. Previously I think task-repetition requirements have been set higher than is ideal partly out of necessity to prevent players from blowing through six months work in one evening.)