Should I give up stock picking (unfortunately I have only made 15K profit since 2018). I can probably only retire at 80 :-(

You just spent wayyyyyyy toooo much time agonising about your portfolio.
Had you invested in stocks with DRIPS, this would have been the outcome. 6% a year overall?Thats quite ok. Had you invested the same same with an extra zero at the end, you wouldn’t complain.

Especially if the drawdowns during that period were similar or worse than VT… if they were substantially better… then maybe you could consider the strategy is somewhat working if the risk-adjusted return is higher.