Should I have seperate brokerage accounts for long term portfolio and daytrading, or is combining them ok?

It’s personal, no right or wrong.

I use the same account. Not sure about IBKR but TOS allows me to group and separate them separately so it’s pretty clear

Really a personal preference. Most maintain a different brokerages mainly for lower fees or premarket / after hours trading options or access instrument exposures. But do take note of the subtle difference in bid-spread price amongst brokers.