The SEC has postponed the decision on XRP and Dogecoin ETF filings by Grayscale Investments and 21Shares.The new decision deadlines are set for mid-June, showing the SEC's cautious approach to altcoins.Both Dogecoin and XRP have seen minor price upticks despite the regulatory holdups.The delays in ETF approvals for altcoins are common, with the SEC using the full review period granted under its rules.