My split for taxable accounts is 65% US, 35% international, which reflects my perception that is slightly skeptical of the health of international markets in the long-term, but otherwise acknowledges the benefits of international diversification. My tax advantaged accounts are two target-date funds, VFFVX (Vanguard 2055 - Roth IRA) and LIVKX (Black Rock 2055 - 401(k)), which are more in line with 60/40.
It has been a bit hard in recent years to watch the outsized performance of US stocks, and the FOMO of being 100% in US equities, but then I realize that this is just my emotions playing tricks, and that to Sell Low and Buy High is exactly the wrong thing to do. Also, I'm overall happy with my returns even if they could have been higher being 100% US. It would be great to see International catch up in the next 10 years, but if that doesn't happen it's also OK.