Controlling 3V3 relay from 2V8 (VL53L1X) GPIO output with PNP transistor
No - That's not going to be 'guaranteed' to work always.  The problem is your logic control signal can only go to max 2.8V, but the VCC is 3.3V.  Like you say, that's &quot;only 0.5V&quot; and &quot;in theory&quot; the transistor won't turn on until there's 0.7V difference there.  But with such a small margin, you can't be assured that always the transistor would be completely off.   They really don't have a hard-fixed cutoff voltage like that - It's more of a range.  That's why there are extra transistors in the other referenced link. They allow for the base of the PNP transistor to get up to the same voltage as &quot;VCC&quot;, thus ensuring that transistor is off.
Understand your concern about 'more parts = higher likelyhood of failure&quot;.  That's not really my experience....  IMO it's more like &quot;The harder you drive the parts, the more likely to fail&quot;.   If you're being very gentle with the parts - operating them very far from their maximum voltage, current &amp; power limits -  resistors and transistors will last pretty much forever.  Relays are another story....  Do you really need to have a relay - i.e. you really need the electrical isolation???  Relays are mechanical devices and as such, they definitely will eventually fail.