-snip-
Buying bitcoin at once is not easy so buy little by little with different percentage of money so then you can easily collect your bitcoin in different prices with different percentage. We should not wait this time for more decrease because now price will go higher and by waiting we can miss the better days of investment.
Now the price is 68k$ so we don't have any guarantee about the ups and downs but we know that halving will move the price in upward direction therefore choose bitcoin at any price as current price is more down as compared to the price originating after halving and it will stay longer until the end of this year.
Not everyone can afford to buy 1 bitcoin nowadays, but there are many people who can afford it and it all depends on the budget that each investor has. Buying with DCA is good, even if you can afford to buy 1 bitcoin at a time. DCA will hopefully get them a lower average price than buy with lump sum, so don't ignore that buying strategy even if you can afford to buy all at once.
You may be right, prices are still difficult to predict even before the halving. An increase is certainly expected, but in this situation panic may occur more easily because there are many new investors who do not yet have good psychology about the market. You must be aware that not everyone is able to control themselves when market volatility becomes high, so the potential for correction cannot be ignored at all.